Donald Trump told the Qatari emir that he was not making enough progress in the battle against terrorism.
In his New York meeting with Sheikh Tamim, the US president stressed “the importance of Qatar taking additional steps to follow through on commitments from the Riyadh Summit to cut off funding for terrorists, discredit extremist ideology and defeat terrorist groups”, the White House said.
He was referring to a summit hosted by the Saudi-led Islamic Military Alliance against terrorism in Riyadh in May, which Mr Trump attended.
He said the Qatar crisis needed to be resolved and Gulf unity restored to “counter the threat of Iran”.
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The two men spoke shortly after the emir’s speech to the General Assembly in New York in which he called for dialogue between Gulf countries and Iran.
The UAE, Saudi Arabia, Bahrain and Egypt cut economic and diplomatic ties with Qatar on June 5 over its support for terrorism and interference in the internal affairs of its neighbours.
Kuwait has taken the lead in mediation to resolve the crisis between Qatar and the quartet of Arab countries.
Lawrence Silverman, the US ambassador to Kuwait, said Washington was “extremely appreciative” of Kuwaiti emir Sheikh Sabah’s mediation and that Mr Trump’s involvement had come at the emir’s request.
Mr Silverman said the president was willing to mediate in the dispute but that its efforts must be synchronised with Kuwait’s. “We have to see what is necessary”, in bringing together the two sides, he said.
In his meeting with Sheikh Tamim on Tuesday, Mr Trump said he had “a very strong feeling” the row would “be solved pretty quickly”.
Tehran and Turkey have been the two major suppliers of Qatar’s food imports since the boycott began on June 5.
Last month, The National reported that Doha was considering opening up trade routes through Iran to bring in Turkish products.
In his address to the General Assembly, Sheikh Tamim called “for an unconditional dialogue based on mutual respect for sovereignty”.
Dialogue between Saudi Arabia and Qatar was suspended this month after the Saudi foreign ministry said Doha had distorted facts.
It came just after a phone call between Sheikh Tamim and Saudi Crown Prince Mohammed bin Salman indicated a possible start to resolving the crisis.
The call was the first publicly announced contact between the two countries since the row erupted.