Iran's foreign minister on Thursday brushed aside demands from the major industrialized nations to respond by July 5 to an international offer for Tehran to roll back its uranium enrichment program, saying his nation would need until August.

Foreign Minister Manouchehr Mottaki said Iran had questions about the proposal that will be raised in talks expected early next month with Javier Solana, the European Union's foreign policy chief. The questions need to be answered so Tehran can respond in August, he said.

"The Islamic Republic of Iran is seriously and carefully reviewing the proposed package," he said. "Questions and ambiguities on the Iranian side are pending. Therefore, we welcome the discussions and negotiations for clarification of those ambiguities."

Mottaki's remarks contradicted his own statements published Wednesday in the German weekly magazine Stern, which quoted him as saying his country may respond before the Group of Eight summit in St. Petersburg, Russia, which starts July 15.

Earlier Thursday, foreign ministers of the Group of Eight meeting in Moscow expressed disappointment at the absence of an official Iranian response to a package of incentives from key global powers to try to persuade Iran to roll back its uranium enrichment program, which can be used to produce nuclear energy or nuclear weapons.

The ministers from the United States, Russia, Britain, France, Germany, Japan, Italy and Canada said they expected to hear "a clear and substantive Iranian response to these proposals" at a meeting on July 5 between Solana and Iran's chief negotiator Ali Larijani.

Mottaki, asked about the Group of Eight request for a response by July 5, noted that when Solana presented the package to the Iranians in Tehran "we did not agree on any specific date to respond."

"The response of the Islamic Republic of Iran to the proposed package ... is clear and will be substantive but ... the proposed package contains questions and ambiguities which must be clear," he said.

"Some of these ambiguities may be responded by Mr. Solana," Mottaki said, but some questions may need "a substantive response" from the six countries that drafted the incentive package, the United States, Russia, China, Britain, France and Germany.

The Iranian minister said the government set up committees to review different aspects of the package because it wanted careful consideration of all aspects. Presumably, the committees would also consider any responses from the six nations that proposed the package.

Mottaki rejected claims that Iran was playing for time, saying the proposal took months to prepare.

Since the issue is important, he said, "I think the time until August is not a long time for submitting a response — and that's very natural and normal."

"I've said that such response will be in August. I didn't say early August or mid-August," he said.

The package seeks to persuade Tehran to impose a long-term moratorium on uranium enrichment. In return, it offers incentives including peaceful Western nuclear technology, the lifting of some sanctions, trade opportunities, U.S. spare parts for Iran's aging fleet of jetliners, and U.S. participation in negotiations with Tehran.

Mottaki did not give a date for the Larijani-Solana talks but confirmed that such a meeting would take place. The meeting would be the first since they met in Tehran on June 6.

Mottaki's remarks echoed comments made by Larijani, who has said the proposals contained "positive steps" but talks were needed to clear up ambiguities.

Iranian President Mahmoud Ahmadinejad has also said the government will not respond officially until at least mid-August. Europe has been pressing for a quicker reply and U.S. Ambassador John Bolton had said the United States wanted a response before Thursday's Group of Eight ministerial meeting in Moscow.

Mottaki reiterated that Iran has a right to enrich uranium for peaceful nuclear energy under the Nuclear Nonproliferation Treaty and an obligation to allow inspections by the International Atomic Energy Agency, which take place on a regular basis. He also reiterated that Iran believes in global disarmament for all weapons of mass destruction.