Japanese opposition leaders and consumer groups this week criticized a tentative agreement to lift a ban on U.S. beef imports, calling it a political gift from Prime Minister Junichiro Koizumi to President Bush before the U.S. election.

The Bush administration announced the accord over the weekend and hailed the resumption of some U.S. beef shipments to Japan in "a matter of weeks," but some Japanese officials said imports are unlikely for at least six months.

Japan's 10-month beef ban -- imposed after a cow in Washington state was found to have mad cow disease last December -- has been a rare problem in U.S.-Japan relations, closing off the single largest foreign market for the $30 billion U.S. cattle industry. After months of unsuccessful talks, Japanese and U.S. officials said they reached a "framework" agreement, and U.S. Agriculture Undersecretary J.B. Penn said Saturday that some American beef shipments to Japan would resume soon.

But Japanese officials familiar with the agreement offered a less optimistic assessment, saying that the deal imposes no specific deadline to lift the ban and that disputes over inspection guidelines and requirements for public hearings would delay the imports.

Even then, Japan could allow only a fraction of the $1.4 billion worth of U.S. beef imported prior to the ban, officials said.

Since the ban, Japan has turned to Australia for much of its beef, and that trade seems to be thriving.

"It is going to take time before any U.S. beef can come back into Japan," said one high-ranking Japanese government official familiar with the deal. "This is not going to happen that quickly."

U.S. and Japanese officials said that Bush, who has the endorsement and financial backing of the National Cattlemen's Beef Association, had asked Koizumi to lift the ban when the two last met, in New York City in September.

Koizumi is facing pressure from Japanese consumer groups, however, to resist U.S. imports until the U.S. government agrees to the same strict inspection requirements that Japanese beef now undergoes. The issue has been especially sensitive in Japan because health officials have found 15 animals with the infection. Japan has for some time required that all cattle be tested for mad cow disease before entering the food supply, and so any change in that position is significant.

Opposition politicians charged that while the agreement leaves Japan's options open, Koizumi was giving Bush the right to claim last-minute progress on an issue dear to battleground states such as Colorado, and to South Dakota, where Senate Minority Leader Thomas A. Daschle is battling for reelection.

"This agreement's chief accomplishment is allowing Mr. Koizumi to help out Mr. Bush ahead of the U.S. election," said Muneaki Samejima, a prominent legislator from Japan's opposition Democratic Party. "After the election, there is still no guarantee of when Japan will import U.S. beef again. . . . Japan should not interfere in other countries' elections."

Koizumi aides and U.S. officials in Tokyo denied any connection to the U.S. presidential election. "The date of the presidential election in the U.S. has nothing to do with the agreement reached," said Yu Kameoka, a Koizumi spokesman.

But Koizumi is nevertheless coming under extraordinarily criticism for his outspoken support of Bush.

Earlier this month, Koizumi told reporters: "Since I'm well-acquainted with President Bush, I want him to carry on."

Japan's beef ban has been viewed as a problem in the Bush-Koizumi relationship. After months of deadlocked talks, Penn arrived in Tokyo last week, where negotiators held three days of heated meetings. At a news conference on Saturday, Penn conceded that the Japanese still had to go through regulatory processes, plant inspections and risk assessments. But when asked how long it would take before import shipments resumed, he said "We are talking a matter of weeks."

To reach the tentative deal, the U.S. side agreed to eventually restrict imports to beef from cattle less than 20 months old. The limit was set because that is the earliest age at which Japanese testing on domestic herds has detected mad cow disease, the fatal brain-wasting disease clinically known as bovine spongiform encephalopathy.

But Japanese and U.S. officials must still agree on how to determine the age of imported U.S. beef. American officials have said Japan's insistence on birth records for cattle is unworkable because few U.S. slaughterhouses keep such documents. The Japanese have similarly questioned U.S. suggestions that bone density and meat color can be an age determinant. The two agreed last week to set up a panel of scientists from both sides to come up with guidelines agreeable to both nations.

But even after new guidelines are established, obstacles to resumed sales include submission to a Japanese health commission for review and public hearings, at which consumer groups will oppose resumed imports.

"We're very worried that the diplomatic negotiations are being put ahead of the domestic debate," said Hiroko Mizuhara, secretary general of the Consumers Union of Japan. "We need more time to examine this. . . . It is strange to hurry up on diplomatic negotiations while all these concerns are unsolved. . . . Prime Minister Koizumi wants to help President Bush; other than that, there are no reasons why we should have to resume beef imports."

In Washington, meanwhile, the Agriculture Department announced on Tuesday that Taiwan has agreed to resume imports of U.S. beef and beef products, pending a final round of inspections.

"Our goal is a return to normal beef trade as quickly as possible," Agriculture Secretary Ann M. Veneman said in a statement. Taiwan imported $325 million worth of U.S. beef and beef products in 2003.

Staff writer Marc Kaufman in Washington and special correspondents Sachiko Sakamaki and Akiko Yamamoto contributed to this report.

A Japanese meat dealer examines a cattle carcass in Tokyo. Japan seeks tighter U.S. beef inspections for mad cow disease.Japanese Prime Minister Junichiro Koizumi and President Bush met last month in New York, and Bush asked Koizumi to lift the beef import ban.