McConnell comes to McCain's defense on Senate floor: 'You’d rather be on his side than not'

The Senate majority leader has clashed with McCain, but supported him Monday.

McConnell had tweeted earlier in the day that he visited with McCain, who is battling brain cancer, over the weekend and said, "I shared my gratitude -- all of our gratitude -- for his service and his sacrifice" as a member of the military.

McConnell has had a back-and-forth relationship with McCain, something he admitted to in his speech Monday, but he offered nothing but praise for the senator during his current plight.

McConnell said the two Republican senators have shared a friendship for 30 years. McConnell has served as senator from Kentucky since 1985, while McCain was elected just one year later to serve Arizona.

"We had some laughs and even reminisced about the battles; sometimes we were on the same side, and sometimes we weren’t," McConnell said from the Senate floor Monday. "But one thing about our colleague, John McCain -- you’d rather be on his side than not."

On Monday, McConnell took the opposite tact, praising the war "hero."

"We all know his story all too well: a genuine American hero. We admire the tenacity and the grit that it took to survive those 5 1/2 years in the 'Hanoi Hilton,'" McConnell said. "And the way he refused to go home early -- as he certainly could have -- given the prominence of his father’s position in the Navy."

It wasn't long ago that McCain and McConnell were feuding. Last summer, McConnell drove an effort to repeal Obamacare with a so-called "skinny repeal." McCain dramatically entered the Senate chambers and voted "no" -- which killed the repeal -- to the applause of Democrats and sour looks from Republicans, including McConnell. After the vote, McConnell called the defeat "a disappointment indeed."

ABC News' Tara Palmeri contributed to this report.