White House Press Secretary Josh Earnest on Monday urged members of Congress to judge the deal with Iran over its nuclear program based "on its merits".

This comes after both the United Nations Security Council and the European Union endorsed the Iran nuclear deal, a first step toward lifting Europe's economic sanctions against Tehran that the bloc hopes will send a signal that the U.S. Congress will follow.

Secretary of State John Kerry, Energy Secretary Ernest Moniz and Treasury Secretary Jack Lew will hold two classified briefings on the Iran nuclear deal on Capitol Hill on Wednesday for members of each chamber of the U.S. Congress, Earnest also said.

US lawmakers have 60 days to review the agreement. The Obama administration is working to win over enough Democratic lawmakers to offset strong Republican opposition to the deal.