Led by Saudi Arabia, Egypt, Bahrain and United Arab Emirates have blamed Qatar for "financing, adopting and sheltering extremists", and alleged that it supports terrorist groups ranging from the Muslim Brotherhood and the Islamic State to the Iran-backed Houthi rebels.
"During my recent trip to the Middle East I stated that there can no longer be funding of Radical Ideology. Leaders pointed to Qatar - look!" Trump tweeted.
"So good to see the Saudi Arabia visit with the King and 50 countries already paying off. They said they would take a hard line on funding, extremism, and all reference was pointing to Qatar," he said.
"Perhaps this will be the beginning of the end to the horror of terrorism!" Trump said.
Trump last month visited Saudi Arabia during which he addressed leaders of 50 Muslim countries including Afghanistan and Pakistan.
Members of the Gulf Cooperation Countries signed a memorandum of understanding with the US to make it illegal in their countries for raising funds for terrorist and extremist organisations.
Trump also slammed the mainstream American media.
"Sorry folks, but if I would have relied on the Fake News of CNN, NBC, ABC, CBS, washpost or nytimes, I would have had ZERO chance winning WH," he said in yet another tweet.
"The FAKE MSM is working so hard trying to get me not to use Social Media. They hate that I can get the honest and unfiltered message out," he wrote.
A day earlier, the White House had said that Trump is committed to have conversations with all of the people involved in that process, with all of those countries.
"We want to continue to deescalate that. And at this point, we're continuing to work with each of those partners," the White House Principal Deputy Press Secretary Sarah Sanders told reporters.
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