ANKARA, Turkey - The United States and other world powers are willing to consider an Iranian proposal that would allow the country to keep some of its uranium enrichment program intact instead of dismantling it completely, foreign government officials said Tuesday.

On the eve of talks between top Iranian envoy Ali Larijani and Javier Solana, the European Union's foreign policy chief, the officials — some of them diplomats, others based in their capitals — said the discussions were key because for the first time they could try to sidestep the deadlock over enrichment by trying to agree on a new definition of the term.

The officials were familiar with the negotiations with Iran or specialized in non-proliferation issues......