The United States has proposed a 20-year suspension of uranium enrichment in Iran as part of ongoing negotiations, according to sources familiar with the talks. Iran countered with a proposal for a shorter suspension period, described as a "single-digit" number of years. The U.S. also demanded the removal of all highly enriched uranium from Iran, suggesting a supervised dilution process as an alternative. Disagreements over Iran's nuclear program, particularly the cessation of uranium enrichment and the handling of existing stockpiles, remain significant hurdles in reaching an agreement. Mediators from Pakistan, Egypt, and Turkey are involved in efforts to resolve these issues before the April 21 ceasefire deadline. Despite Iran's belief that a preliminary deal was close, U.S. Vice President Vance's press conference, which accused Iran and announced the U.S. delegation's departure from Islamabad, has added to the tensions.