China is not likely to approve a fourth round of sanctions against Iran while there is still room for negotiations, experts have said, as another round of talks between six key powers ended on Saturday without an agreement.

China, Britain, France, Russia and the United States - the five permanent United Nations Security Council members - and Germany attended the meeting at the European Union Mission to the United Nations in midtown Manhattan, New York City, Xinhua reported.

"We had a very sober assessment," Russian Deputy Foreign Minister Sergei Ryabkov said.

"It is inconclusive in the sense that we did not make any decisions right away", but there is "still time for meaningful political engagement and efforts to find a solution", AFP and the Washington Post quoted the minister as saying.

Beijing was represented by Kang Yong, a counselor of China's mission to the UN. He was the lowest-level diplomat at the meeting, Bloomberg reported. He did not speak to reporters.

But Foreign Minister Yang Jiechi reiterated on Friday that the Iranian issue should be resolved through "peaceful diplomatic negotiations".

Although no deal was reached at Saturday's meeting, participating nations agreed to consider "further measures by the UN Security Council", the New York Times said.

But Chinese analysts said Beijing is unlikely to support further sanctions.

"It will be difficult for sanctions to be pushed forward, as China and Russia are not willing to do so when neither the United States nor Iran has completely abandoned peaceful talks," China's former ambassador to Iran, Hua Liming, told China Daily yesterday. 

US Secretary of State Hillary Clinton said last Monday that the Obama administration believed the best method to pressure Iran to become transparent about its nuclear ambitions is to pass new sanctions that impact its ruling elite.

"The Obama administration hasn't made any actual progress concerning Iran and the Middle East, let alone achieving any goals, since it took office," Hua said.

Hua also said the US might modify the new sanctions to gain support from China and Russia.

Bloomberg reported on Saturday that the sanctions would most likely target Iranian shipping companies that have violated the UN arms embargo. They would also likely bar nations and international lenders, such as the World Bank, from giving Iran any grants, loans or other financial aid, except for humanitarian or development purposes.

The sanctions would also target Iran's Revolutionary Guard Corps (IRGC). According to the Council on Foreign Relations' website, the IRGC has evolved into one of the country's most influential domestic institutions. It controls strategic industries, commercial services and black-market enterprises.

"The Western powers will not get what they want from the six-nation talks," said Yin Gang, a Middle East studies expert at the Chinese Academy of Social Sciences.

Yin said China will, however, support the major powers' demand to halt Iran's enrichment program in Qom.

The uranium enrichment plant hidden inside a mountain near the holy city of Qom was revealed in September.

"Clearly (the program) violates the rules of the International Atomic Energy Agency (IAEA), while China has always supported the IAEA," Yin said.

The Security Council has imposed three rounds of sanctions on Iran over suspicions that it is hiding nuclear activities. It fears Iran could retool its enrichment program, which makes low-grade uranium to generate nuclear power, to produce weapons-grade uranium used for nuclear warheads. Iran denies the accusation and insists its program is for peaceful purposes, the Washington Post said.