Story highlights Trump's tweeted Tuesday in praise of the Gulf nations' move against Qatar

Qatar is home to one of the largest US military bases in the region

Washington (CNN) President Donald Trump changed course on Qatar Wednesday, a day after praising a move by other Gulf nations to sever diplomatic relations with Doha, which hosts a US military base crucial to the fight against ISIS.

In a phone call with the Qatari Emir, Trump extended an olive branch, offering to help the parties resolve their differences by inviting them to a White House meeting if necessary. The outreach came as US officials told CNN they were observing increased Qatari military activity as the country placed its forces on the highest state of alert over fears of an military incursion.

Trump's new tone echoed that of his secretaries of Defense and State, who emphasized Tuesday the need for Gulf unity and the importance of the US partnership with Qatar, home to the Al Udeid Air Base , the main regional center for air missions against ISIS.

JUST WATCHED Trump claims credit for Arab rift with Qatar Replay More Videos ... MUST WATCH Trump claims credit for Arab rift with Qatar 01:33

Trump's phone call Wednesday made for a stark contrast to a series of tweets he sent Tuesday, in which he appeared to throw his weight behind the effort by Saudi Arabia, the United Arab Emirates, Bahrain and Egypt, along with Yemen, the Maldives and Libya, to ostracize Qatar

Referring to his May trip to the region, Trump tweeted that it was "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. Perhaps this will be the beginning of the end to the horror of terrorism!"

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