After his inauguration, Donald Trump officially became the 45th President of the United States. Despite becoming the new commander in chief, some Republicans are still not on board.

McCain on Trump

Ever since Donald Trump announced his candidacy for president, the Republican Party has been split in their support for the billionaire real estate mogul. Heading into the Republican National Convention, the "Never Trump" movement picked up steam, voicing their opposition to the former host of "The Apprentice." Once Trump was named the party's nominee for president, Republicans rallied by his side, but as controversy continued to hover over him, Trump was unable to gain full support from his party.

As seen on ABC's "The Week" on January 22, Sen. John McCain expressed his concern about the new president.

Joining ABC host George Stephanopoulos was Sen. John McCain, who was asked whether or not he had "utmost confidence" in Donald Trump. "I do not know, George. I do not know," McCain admitted, before adding, "He has made so many comments that are contradictory."

John McCain did give a glimpse of hope, saying that he supported the majority of Trump's cabinet selections, calling them a "encouraging sign." The Arizona senator did cave and announced he will support Rex Tiller for the job as Secretary of State, despite expressing concern over the former Exxon Mobil CEO's ties to Russian and President Vladimir Putin.

This isn't the first time that McCain has voiced his opposition to Trump. During the election, the new president came under fire for questioning if the senator was a war hero due to being taken as a POW during the Vietnam War, then following the election, McCain threatened to sue Trump if he tried to bring back the use of waterboarding and other forms of torture.

Moving forward

While there continues to be some push back against Donald Trump, the Republicans are expected to come together enough to get much of their agenda into law. However, growing opposition to Trump has only continued, with a Women's March bringing out over a million protesters over the weekend just a day after Inauguration Day.