U.S. imposes new, "hard-hitting" sanctions on Iran amid tensions

U.S. President Donald Trump announced on Monday that his country is imposing new and "hard-hitting" sanctions on Iran amid high tensions between Washington and Tehran.

Trump signed an executive order at the White House on Monday, slapping additional economic sanctions on Iran. Trump told reporters that the targets of the new sanctions include Iran's Supreme Leader Ayatollah Ali Khamenei.

The new action is "imposing hard-hitting sanctions on the Supreme Leader of Iran and the office of the Supreme Leader of Iran and many others," said Trump.

The U.S. president claimed Monday's move came after "a series of aggressive behaviors by the Iranian regime in recent weeks" including shooting down a U.S. drone.

U.S. Treasury Secretary Steven Mnuchin revealed in a following press conference that the new executive order will freeze billions of additional dollars in Iranian assets.

Tensions remain high in the region over Iran's downing of a U.S. military drone last week and Trump's decision to abort imminent military strikes against Iran in retaliation.

Over the past month, Washington has beefed up its military forces in the Middle East, which Iran described as a disturbing element.

Iranian President Hassan Rouhani said on Sunday that military intervention of the United States in the region has caused problems for the nations, semi-official Fars news agency reported.