To update prices and add details

May 4 (Reuters) - Gold prices fell in thin trading on Monday , pressured by inflation concerns that overshadowed the outlook for U.S. monetary policy, while markets awaited developments in negotiations between the United States and Iran.

Spot gold fell 0.5 percent to $ 4,588.71 an ounce by 06:55 GMT. U.S. gold futures for June delivery declined 0.9 percent to $ 4,600.60 .

Markets in China, Japan and Britain were closed due to holidays.

Federal Reserve Chairman Jerome Powell concluded his eight years at the helm of the central bank last Wednesday with a decision to keep interest rates unchanged amid growing concerns about inflation.

Tim Waterer, chief market analyst at KCM Trade, said, "Gold continues to be affected by the ongoing fallout from the Fed's dovish messages last week, particularly the prominent dissenting voices rejecting further monetary easing."

Higher oil prices could encourage central banks to keep interest rates high for longer, which would put pressure on non-yielding assets such as gold.

Oil prices have fallen but remain above $100 a barrel amid uncertainty over a possible deal between the United States and Iran.

US President Donald Trump said Washington would begin efforts on Monday to help free ships stuck in the Gulf due to the conflict between the United States and Israel and Iran, after an oil tanker reported being hit by unidentified projectiles in the Strait of Hormuz.

Iranian state media reported that Washington responded to the 14-point Iranian proposal through Pakistan, and that Tehran is now studying it.

As for other precious metals, silver fell 0.6 percent to $ 74.91 an ounce in spot trading, platinum was steady at $1,989, while palladium slipped 0.4 percent to $ 1,519.78 .