Washington, September 7 (RHC)-- U.S. President Barack Obama has thanked former secretary of state Colin Powell for announcing his support of the Iran nuclear agreement. Obama expressed his gratitude to the veteran African-American statesman in a message posted on his Twitter account on Sunday.

The U.S. president drew attention to Powell's rationale for supporting the deal that Republicans, who control both houses of Congress, almost unanimously oppose, because they say it gives too many concessions to Iran and threatens the security of Israel.

"Thank you, Colin, for putting your experience and expertise behind this important initiative for our country," the U.S. president tweeted.

Powell, a Republican and retired four-star general in the U.S. Army, told NBC News earlier on Sunday: "It's a pretty good deal.” He dismissed concerns put forward by opponents about independent inspectors’ ability to verify that Iran is complying with the agreement.

“I think a very vigorous verification regime has been put into place," said Powell, who served under President George W. Bush from 2001 to 2005. "I say, we have a deal, let's see how they implement the deal. If they don't implement it, bail out. None of our options are gone," he added.