TEHRAN – Iran has prepared an updated nuclear proposal and is ready to hold negotiations with world powers, state-run Iranian television quoted the Islamic Republic's chief nuclear negotiator as saying on Tuesday.

U.S. President Barack Obama has given Iran until later this month to take up a six-power offer of talks on trade benefits if it shelves nuclear fuel production, or face harsher sanctions.

Germany has said it will host high-level talks this week with the United States, China, France, Britain and Russia on what to do about Iran's contentious nuclear program.

Iran has rejected demands to halt uranium enrichment or even freeze it at current levels, a process it says is for peaceful energy but which the West suspects is aimed at developing an atomic arsenal.

Iran has prepared an updated nuclear proposal and is ready to resume negotiations with world powers, chief nuclear negotiator Saeed Jalili was quoted as saying by al-Alam, Iran's Arabic-language satellite television channel.

Iran ready to offer new nuclear package, Press TV, the Islamic Republic's English-language state television, said in a scrolling headline.

We hope a new round of talks will be held to help us make the world full of progress, justice and peace, Press TV quoted Jalili as saying. It added that Jalili hoped Iran's revised proposal could serve as a basis for talks with the big powers.

Asked about the report of Iran's readiness for talks, a Western diplomat told Reuters in Vienna: If it is confirmed ... it would of course be very welcome.

German Chancellor Angela Merkel said on Monday Iran should realize how very serious the Obama's September is.

ECONOMIC INCENTIVES

An International Atomic Energy Agency report last week said Iran had not heeded U.N. Security Council demands that it stop enriching uranium and open up to IAEA investigators to exclude the possibility of military dimensions to its nuclear activity.

Washington and its allies may target Iran's gasoline imports in a possible 4th round of sanctions. Iran, the world's number five oil exporter, imports up to 40 percent of its gasoline.

Russia and China have reluctantly backed three rounds of moderate sanctions touching on Iran's nuclear and missile industries since 2006, though they managed to water down some measures before voting for them in the U.N. Security Council.

President Mahmoud Ahmadinejad said in April, before his disputed re-election in June, that Iran had prepared its own proposals to end the stalemate. His foreign minister said they included political, security and international issues.

It was unclear whether Iran's counter offer would be essentially different from previous ill-fated exchanges.

The six powers originally offered Iran trade, financial and diplomatic incentives in 2006 in exchange for a suspension of enrichment. Iran's response hinted at some flexibility but ruled out suspension as a precondition for talks.

In June 2008, the six improved the offer but retained the precondition. In reply, Iran said it wanted to negotiate a broader peace and security deal -- dismissed by Western officials as vague and irrelevant -- and rejected any condescending formula to shelve its nuclear program.

Diplomats say Western officials have suggested a face-saving way into talks could be a verified freeze in enrichment expansion, with suspension still the goal in exchange for benefits to Iran. But Tehran has ruled out any such freeze.

(Additional reporting by Sylvia Westall in Vienna; Writing by Fredrik Dahl; Editing by Mark Heinrich and Jon Hemming)