LONDON, Feb. 26 -- Representatives of the five permanent members of the U.N. Security Council and Germany said after meeting in London on Monday that they were committed to seeking a negotiated solution with Iran, which has defied a U.N. order to halt its uranium enrichment program.

In Washington, meanwhile, State Department spokesman Sean McCormack told reporters that the six nations had "agreed on the fact that they will go forward with a U.N. sanctions resolution."

McCormack said the six nations -- the United States, Britain, France, China, Russia and Germany -- wanted Iran to negotiate. But he also said, "We are equally committed to sending the message to the Iranian government: Should they choose not to proceed down that pathway, then there will be consequences."

Last week, the International Atomic Energy Agency issued a report saying that rather than halting its uranium enrichment program, Iran had expanded it.

During a visit Saturday to Sydney, Vice President Cheney told reporters that "all options are still on the table" for dealing with Iran, raising concerns that the United States was considering a possible military strike.

The United States accuses Iran of secretly using its nuclear program in an effort to build atomic weapons. The Tehran government insists its program is solely for energy purposes and that it has no intention of stopping its uranium enrichment as demanded by the Security Council.

Officials at the talks sought to play down any rising confrontation. John Sawers, the British official chairing Monday's meeting, issued a statement saying that the group had "considered how best to reengage with Iran. We are all committed to seeking a negotiated solution."

Not all parties agree on the seriousness of the threat from Iran or how best to contain it. Of the five permanent members of the U.N. Security Council, Russia and China have resisted tough sanctions.

In December, the Security Council banned countries from supplying Iran with technology that could be used in its nuclear and missile programs and froze the assets of certain companies and individuals. Now wider economic sanctions are being considered, along with a travel ban on some officials.

Officials from the six nations involved in the talks are to continue discussions by phone on Thursday.