South Carolina Sen. Lindsey Graham was pressed on his transition to an amicable relationship with President Donald Trump in spite of their often viral clashes before the 2016 election.

At one point during the campaign, Trump became so frustrated with Graham (R) that he shared the senator's cell phone number with the public.

CNN host Kate Bolduan on Friday asked Graham about several recent statements and decisions by Trump and why he continues to defend the president.

Graham said he still clashes with Trump from time to time but believes that Trump is trying to do the right thing for the country.

Bolduan asked about Trump's comment that President Obama was to blame for Russia annexing Crimea.

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Graham said he doesn't agree with Trump on that point, but added that the president cannot be to blame for all the world's problems.

"When can you trust the words coming out of his mouth?" Bolduan asked, adding that Graham used to "hate" Trump.

"I know how the game is played, I don't give a damn," Graham said of being considered "two-faced" for working with Trump, but a "hero" for working with Obama.

"If you don't like me working with President Trump to make the world a better place, I don't give a s***," Graham said.

Watch the segment above. Relevant video begins at approximately the 11:00 mark.

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