The United States has announced it would send a high-ranking official to Geneva for talks intended to encourage Iran to abandon its nuclear program.

William J. Burns, the under secretary of state for political affairs and the number three official at the State Department, will attend a meeting on Saturday with European Union foreign policy chief Javier Solana and Iran’s nuclear negotiator, Saeed Jalili. Iran at first rejected a United Nations offer of sanctions and economic incentives, but in recent weeks senior Iranian officials have indicated Tehran might be more open to compromise than first thought.

The contact will be the highest-level US-Iran contact since Shiite extremists raided the United States embassy in Tehran in 1979 and held 52 Americans hostage for 444 days.