Washington (CNN) President Donald Trump is taking another swing at his relations with some former rivals.

Trump golfed with Sen. Lindsey Graham on Saturday, according to the White House, after hitting the links with the South Carolina Republican on Monday. Then on Sunday, he planned to golf with Kentucky Republican Sen. Rand Paul, who backed his recent efforts on health care and received a pen as well as a friendly pat on the shoulder when Trump issued the executive order on Thursday that is designed to increase competition and choice in markets.

The warming ties -- Trump and the senators were bitter GOP primary opponents and have occasionally engaged in public feuding since the inauguration -- come as the President's relations are fraying with Senate Republicans just as he's relying on them to help pass his agenda.

Trump engaged in a public spat with Tennessee Sen. Bob Corker last week, and Maine Sen. Susan Collins, who helped thwart GOP efforts to repeal Obamacare, announced Friday that she will bypass a gubernatorial run and stay in the Senate. Meanwhile, Trump's former chief strategist, Steve Bannon, has declared "war" on the Republican establishment and, in particular, Senate Majority Leader Mitch McConnell.

Republicans control 52 Senate seats, which means they often can't afford to lose more than two votes to pass major legislation.