Zimbabwe's parliament voted Tuesday to give President Robert Mugabe new constitutional powers to seize farmland and to restrict travel by government opponents in a country whose government is already regarded as among the most repressive in Africa.

The parliament, flush with new members from Mugabe's ruling party after a March legislative election that was denounced by many international observers as rigged, cast 103 votes for the constitutional changes, enough for the two-thirds majority needed in the body of 150 members. News reports from Harare, the Zimbabwean capital, said ruling party lawmakers began singing and dancing over the victory.

The practical effect of the changes was hard to predict in a country where the government has already endorsed violent land invasions, demolished hundreds of thousands of homes, shuttered independent newspapers and threatened would-be protesters with arrest and attack.

But opposition leaders predicted that Mugabe, who is expected to swiftly sign the changes into law, would soon revoke their passports, making it more difficult for them to lobby for international pressure against Mugabe's autocratic leadership.

"We are the immediate targets," said Paul Themba Nyathi, spokesman for the opposition Movement for Democratic Change, speaking by phone from Bulawayo, Zimbabwe's second-largest city. "They are going to take away our passports. I'm sure of that."

Nyathi and others, however, said the vote was mainly an act of defiance by Mugabe's government, which has increasingly been isolated by the United Nations and most of the developed world. In July, the United Nations issued a sharply worded report condemning Mugabe's Operation Murambatsvina, or "Drive Out the Rubbish," a demolition campaign that left 700,000 people homeless or without jobs.

"This is them thumbing their nose at the rest of the world," Nyathi said of Tuesday's vote in parliament.

Mugabe's spokesman, George Charamba, could not be reached by phone Tuesday. On state radio, Agriculture Minister Joseph Made praised the new legal restrictions placed on white former farm owners who seek to challenge government confiscations of their land.

"Today is a happy moment," Charamba said, according to the Reuters news service. "This gives us an opportunity as Zimbabweans to be the true owners of the land and to be truly independent."

Faced with hyperinflation, 70 percent unemployment and a paralyzing shortage of fuel, Mugabe has recently sought financial assistance from friendly countries, including South Africa and China. A team from the International Monetary Fund, meanwhile, has been making a final evaluation before deciding whether to expel Zimbabwe for failing to pay $295 million in debt.

But Mugabe, 81, Zimbabwe's ruler since 1980, has steadfastly resisted any political reform, refusing even to meet with opposition leaders.

Among the constitutional changes approved Tuesday was the creation of a 65-member senate, which opponents said would merely give Mugabe more opportunities for patronage by appointing members of his party.

The measure limiting rights of appeal against government land seizures drew strong opposition from lawyers. It also touched a particularly raw nerve politically. Many Zimbabweans date the decline of their once-prosperous economy to the government-sanctioned invasions of white-owned commercial farms that began in 2000.

Although the seizures have been popular with landless peasants who were given farms, agricultural production in Zimbabwe, once regarded as the region's breadbasket, has plummeted so dramatically that millions of Zimbabweans now rely on international food donations each year. The economy also has contracted by at least one-third in that time.

Lovemore Madhuku, a government opponent who chairs a civic group called the National Constitutional Assembly, denounced the changes as contrary to the wishes of Zimbabweans. His group has led efforts to seek a comprehensive review of the constitution.

"We are concerned that government continues to make law without consulting the broad section of our country," Madhuku said by phone from Harare.

Zimbabwe's president, Robert Mugabe, has been increasingly isolated by the United Nations and most developed countries because of his autocratic rule.