By Humeyra Pamuk, Dave Graham and Nandita Bose

BUERGENSTOCK, Switzerland/WASHINGTON, June 23 (Reuters) - The United States waived sanctions on Iran for 60 days from Monday after the first talks under a nascent peace deal, with U.S. President Donald Trump saying he will "do what I have to do" if Iran does not stick to its side of the agreement.

U.S. Vice President JD Vance said talks with Iranian officials in Switzerland had laid a good foundation for a final peace deal, although Iran denied that it had begun discussions of its nuclearprogram.