US Secretary of State Mike Pompeo faces charges of using diplomatic dinners funded by taxpayers' money to lure wealthy and influential Americans to build his own political power base in pursuit of the White House.

The British Times newspaper said Pompeo - seen as one of the most loyal ministers to President Donald Trump - may have ambitions to run for the White House, and that he has been under government scrutiny since last week on the back of dismissing a government official who was examining some of his practices.

State Department officials have raised concerns about the real goals behind Pompeo's "dinner dinners" on a lavish side of the Harry Truman Building, the headquarters of US diplomacy in Washington.

The newspaper pointed out that, unlike the events organized by the 19th US President James Madison where prominent foreign personalities were attending, Pompeo invites for these occasions local politicians, businessmen, media people, faces from the entertainment world, business tycoons and senior judges, and foreign personalities made up only 14% of the invitees.

And she called on figures from the Democratic Party to conduct an investigation into these private banquets, claiming that it "served few of the foreign policy goals", and that it was aimed at strengthening Pompeo public relations.

The American channel "NBC" was the first to reveal these details at a time when Pompeo is facing a wave of criticism against the background of his dismissal of the State Department's Inspector General Steve Linck, who was investigating whether Pompeo had used one of his aides to do personal tasks, such as walking with his dog.

Bob Deminendes, the top Democrat on the Committee on Foreign Relations, sent a letter to the State Department calling for "full accountability" regarding the financing of those dinners, and copies of the letters Pompeo made on those occasions.

About 500 guests attended a total of twenty dinners, enjoyed special artistic entertainment, toured the diplomatic reception rooms, and attended cocktails about an hour before dinner. Guests received invitations from the personal email of Pompeo's wife Susan, among the guests who attended the singer Ripa McIntyre.

These dinners are "a global opportunity to discuss the State Department's mission and the complex foreign policy issues facing the United States," said State Department spokeswoman Morgan Ortagos.

It is believed that State Department Inspector-General Steve Linnick was also scrutinizing the terms of a multi-billion dollar bill to sell arms to Saudi Arabia against the will of Congress.

Pompeo defended the decision to dismiss Linnick, and said, "I recommended President Trump to terminate Steve Linnick's services, frankly I should have done this some time ago. There are allegations that this was retaliation due to some of the investigations that the IGO was involved in, that this is not true." Pompeo also denied accusations that one of his aides used to accompany his dog on a walking class.