TRIPOLI, May 9 (Xinhua) -- Washington's withdrawal from Iran's nuclear deal is a "reckless step" that threatens the Middle East, said Khaled al-Muntaser, a Libya international relations researcher and professor.

"It is a reckless step that has negative implications on the Middle East, as it came after the easing of tension between Tehran and the countries of the region since the deal was signed three years ago," al-Muntaser told Xinhua on Tuesday.

"The entire international community will oppose this withdrawal," said the professor.

U.S. President Donald Trump said in the White House on Tuesday that he will withdraw the United States from the Iran nuclear deal.

In a televised speech, Trump announced the exit and said he will not sign the waiver of nuke-related sanctions against Iran, re-imposing sanctions lifted under the accord.

Iran and the P5+1 (Russia, China, the United States, Britain, France and Germany) held strenuous negotiations in 2015 that ended up with an agreement obliging Tehran to peacefully pursue its nuclear program in return for a complete elimination of all international sanctions.