VIENNA — Iran signaled today it will not meet Western demands for a deal that would move most of its enriched uranium out of the country and delay its gaining the ability to make a nuclear bomb.

Tehran said it needs enriched uranium for nuclear fuel, but the West fears it could be used for weapons. The U.S. said Iran is now one to six years away from being able to make such arms, should it choose to.

Tehran's refusal to give up most of its enriched stock could doom both today's talks and chances of a second round of broader negotiations between Tehran and six world powers on the Islamic Republic's nuclear program.

Today's Vienna talks between Tehran and the U.S., Russia and France, focus on a technical issue with huge strategic ramifications — whether Iran is ready to farm out some of its uranium enrichment program to a foreign country.

Progress would strengthen confidence on the part of the U.S. and five other big powers trying to persuade Iran to dispel fears about its nuclear program that this time Tehran is serious about reducing tensions and ready to build on Oct. 1 Geneva talks with six world powers.