Chairman Bob Corker, a Republican and Ben Cardin, the top Democrat, are working on legislation that would give Congress a say in the implementation of any final deal the US and its partners can reach with Iran in coming weeks. The committee is to vote on the bill on Tuesday.
Obama objects to the bill as it's written and has promised to veto it.
Josh Earnest, the president's spokesman, says Obama yesterday discussed with Corker the commitments Iran had made to limit its nuclear program.
The tentative agreement has to be finalised by June 30. Corker's office confirmed the telephone call but declined to discuss details. Cardin confirmed that he spoke with Obama for about 15 minutes.