China's former president, Jiang Zemin, is strengthening his hold on power by promoting a hard-line approach toward Hong Kong and Taiwan, making it more difficult for the country's new leaders to consider concessions on either issue, according to sources in the government and the ruling Chinese Communist Party.

Jiang and his successor, President Hu Jintao, have not clashed over the policies, the sources said, and Hu also favors a firm stand against Taiwan's push for independence and Hong Kong's demands for democratic reform. But Jiang has limited Hu's room to maneuver in tackling two of the most sensitive problems facing his government, the sources said.

A prolonged struggle for power between Jiang's allies and those who support Hu has created a dynamic in which any senior leader who argues for even a slightly more moderate policy risks being attacked by rivals in the other camp as too weak to govern, said the sources, who spoke on condition of anonymity and said they favor neither faction.

"Policy is being used as a weapon in the power struggle," said one government official with access to the senior leadership. "Under these conditions, no one wants to be soft. Everyone wants to be tougher."

Though Hu took over as the party's general secretary in late 2002 and as president in March 2003, Jiang, 77, continues to wield influence as chief of the nation's military. Sources say he is resisting pressure to retire and to relinquish that post to Hu at a key party meeting later this year and that he is using the challenges posed by Taiwan and Hong Kong to his advantage.

Jiang has also packed the ruling Politburo Standing Committee with his allies and may be considering an attempt to have Hu replaced.

The rivalry between Jiang and Hu has led some officials to complain in private that the party has "two centers," a phrase used in Chinese politics to describe a dangerous split in the leadership. Some expressed concern about the risk of political instability and paralysis in government at a time when the party is confronting rising social discontent and managing a painful transition to capitalism.

The uncertainty over the leadership has slowed party decision-making on various issues. For example, Hu and his partner, Prime Minister Wen Jiabao, want to devote resources to the country's interior and its rusting industrial northeast, while Jiang and his allies are trying to preserve economic benefits for their power base in the Shanghai region, the sources said.

But they said the impact of the rivalry is most evident in Beijing's decision to stand by Hong Kong's unpopular chief executive, Tung Chee-hwa, who was appointed by Jiang, and to rule out direct elections in 2007 to choose his successor. The competition for power has also made any compromise with Taiwanese President Chen Shui-bian less likely, they said.

Tensions across the Taiwan Strait have been running high since Chen narrowly won reelection in March after waging a pro-independence campaign. He has offered to hold talks with China without preconditions, but Beijing has insisted that Chen first acknowledge that Taiwan is part of China. The Beijing government has also threatened to attack the self-governing island if it moves toward formal independence.

Wen has already been criticized by Jiang's camp for not taking a strong enough stand on Taiwan during his trip to the United States last December, even though President Bush issued a strong rebuke of Chen during the visit, party sources said. Wen was also criticized for sounding too conciliatory after visiting Hong Kong on the day of the mass anti-government protests there last July, the sources said.

Jiang further asserted his authority over Hong Kong and Taiwan policy during a tour of southern Guangdong province in January and February that party officials said recalled a similar swing through the region in 1992 by China's last paramount leader, Deng Xiaoping, who was fighting a challenge by party conservatives at the time.

State media did not report Jiang's visit, and government spokesmen declined to comment on it. But local officials confirmed that Jiang spent a few weeks receiving visitors at a guesthouse on an island on the Pearl River in Guangzhou. Employees at a cultural park in nearby Shenzhen also confirmed Jiang's visit, adding that he mounted the stage and danced with Tibetan and Uighur performers.

A party source said Jiang used the trip to emphasize his experience in Taiwanese affairs and the volatility of cross-strait relations by inspecting several military units in Guangdong that would participate in any conflict with Taiwan.

Jiang also held a series of meetings with local officials, academics and businessmen in Shenzhen, located just across the border from Hong Kong, to discuss growing demands for direct elections in the former British colony. During the meetings, party sources said, Jiang outlined a firm response by Beijing and referred to a statement by Deng that "patriots must form the main body" of Hong Kong's leaders.

Days later, according to a senior editor at a party newspaper, the central propaganda department in Beijing called a meeting of state media executives and ordered them to prepare a series of reports highlighting Deng's statement. Vice President Zeng Qinghong, Jiang's most senior aide and his favored candidate to replace Hu, addressed the meeting by telephone and personally delivered instructions, the editor said.

The articles, which appeared on the front page of all major party newspapers, were followed by attacks on pro-democracy figures in Hong Kong as unpatriotic and on U.S. and British support for them as interference in China's internal affairs. Then, in March and April, the Chinese government ruled out elections to choose Hong Kong's next chief executive in 2007 and its entire legislature in 2008.

The decision marked a sharp change in strategy by Beijing, which had adopted a softer line after the July demonstrations and allowed the withdrawal of the strict anti-subversion bill that sparked the protests. Zeng orchestrated the policy shift after assuming control of a new senior leadership committee on Hong Kong affairs, the sources said.

"They're afraid of democracy in Hong Kong," said a person who met with Jiang in Guangdong. "They're afraid if people in the mainland see that Hong Kong can elect its own leaders, they will begin to ask why they can't do the same."

In the past month, three popular radio talk-show hosts in Hong Kong critical of Beijing quit their jobs after receiving threats that they alleged were authorized by the Chinese government.

Several officials acknowledged that Beijing's tough policies in Hong Kong could prompt a backlash. Democracy advocates are organizing another mass demonstration there on July 1, the anniversary of last year's march and the territory's 1997 return to Chinese rule. They are also campaigning to win a majority in legislative elections in September, which they could use to block government legislation and try to force Beijing to compromise on political reform.

But the government official with access to the leadership said such a setback in Hong Kong might not hurt Jiang and his allies. "Even if tough policies produce bad results, you won't be blamed," he said. "But you can always be blamed for being soft, regardless of the results."

He and other sources said Jiang has sought to use the sense of crisis surrounding Hong Kong and Taiwan to bolster his bid to stay on as chairman of the Central Military Commission. Deng stepped down as head of China's military two years after giving up his other posts, and some party elders have called on Jiang to do the same, which would mean retiring late this year, the sources said.

But a party official said that in meetings held during the annual session of the National People's Congress, the Chinese legislature, Jiang argued that he should retain control of the military. In one meeting, the official said, Jiang stunned participants by quoting an ancient Chinese historian's observation that transfers of political power are often accompanied by bloodshed.

Newspapers and magazines controlled by the military have been praising Jiang's role in modernizing the People's Liberation Army and highlighting the risk of war with Taiwan. One magazine published an article discussing strategies that Chinese troops might employ in the event that the United States used nuclear weapons in such a conflict.

State media have also highlighted a proposal to adopt legislation that would write into law the government's threat to attack Taiwan if the island formally declares independence. "The more tense the situation is, the easier it is for Jiang to justify that he should stay in office," said the editor at the party newspaper.

Hu has been careful not to confront Jiang, party sources said, and instead has accepted his criticism, sometimes expressed in letters. In some cases, the sources said, Hu has reversed himself after Jiang objected to a decision.

But Hu has also been steadily appointing allies to fill provincial and municipal posts across the country. And in repeated appearances with impoverished workers and farmers, he and Wen have distinguished themselves from Jiang and won support from a broad cross section of society.

Jiang Zemin, left, then China's president, chatted with his successor, then-Vice President Hu Jintao, before the transition last year. Since then, Jiang's continuing influence has contributed to a rivalry now seen as affecting China's attitude toward Taiwan and Hong Kong.