China and Israel emerged from talks on Iran's nuclear future on Tuesday with each side sticking to divergent positions on whether additional United Nations sanctions would help defuse the standoff.

Foreign Minister Tzipi Livni was in Beijing seeking to persuade China to back tougher economic restrictions on Tehran unless it curtails nuclear activities that Western powers say are aimed at making nuclear weapons.

"We believe that there's a need to enhance the sanctions in order to stop Iran," Livni told a news conference after meetings with senior Chinese officials. "We believe that there is a need for more sanctions in the United Nations Security Council."

Livni added that Iran was abusing other powers' willingness to negotiate and would only rein in its nuclear activities under stiffer sanctions.

Responding to Livni's message, a Chinese Foreign Ministry spokesman underscored his country's stance that a negotiated settlement was still viable.

"We believe that a peaceful resolution of the Iran issue through negotiation is the best choice," spokesman Liu Jianchao told a news conference. "China has always maintained that in international relations sanctions should not be rashly applied."

The exchange of views suggested that Beijing - along with Russia - remains wary of a proposed fresh round of UN sanctions that Israel, Washington and other Western powers want considered. China's permanent seat on the UN Security Council gives it the power to veto such moves.

Iran and the International Atomic Energy Agency agreed in August on a timetable to answer outstanding questions about the country's atomic activities, prompting world powers to postpone a third round of UN sanctions until at least November.

But U.S. officials have said there was no sign that Iran was going to suspend uranium enrichment, and Washington slapped new unilateral sanctions on Tehran last week. Increasingly angry rhetoric between the two sides has also fed speculation of a U.S. military strike.

Iran has shrugged off two earlier rounds of sanctions, which China backed, and Livni has said tougher measures were needed to raise domestic pressure on the Iranian government to make nuclear concessions.

Iran is China's third biggest supplier of imported crude oil, behind Angola and Saudi Arabia.

"We should avoid making the problem more complicated," spokesman Liu said.