Afghanistan, Aug. 18 -- U.S. Senator Chris Murphy has sharply criticized President Donald Trump's approach to Iran's nuclear programme, arguing that Washington currently lacks an effective means of forcing Tehran to abandon its nuclear ambitions.

Speaking amid renewed uncertainty over U.S.-Iran diplomacy, Murphy said Iran was taking advantage of what he described as Trump's weak negotiating position.

"The Iranians are playing Trump and his diplomatic genius," Murphy said, according to Al Jazeera. He argued that Tehran could secure significant economic concessions without giving up major elements of its nuclear programme.

Murphy said Iran could potentially obtain sanctions relief and access to frozen funds without making what he considers...