Washington (CNN) President Donald Trump stopped by the Capitol on Tuesday to join Republican senators for their weekly policy lunch and, according to members who attended, he did not address the hot button issues -- such as comments his aide made about ailing John McCain or his call for helping a US-sanctioned Chinese technology company.

Instead, Trump covered a wide range of policy topics including North Korea, Iran, China and the plan for a US border wall -- as well as making a couple of jokes along the way.

As Trump finished his remarks and the brief question-and-answer portion of the closed-door Republican luncheon began, Sen. Dean Heller, a Republican from Nevada who is up for re-election in November, spoke up about a key Trump policy.

He talked first about the US Embassy opening in Jerusalem. Heller attended that, but then he pivoted to a question about immigration. He asked, according to a source in the room and another source familiar, that Trump hold off on focusing on his border wall until after the midterm elections, but the President was noncommittal.

The border wall and Trump's desire to build it have been a cornerstone of his presidency, but the wall is complicated for senators and House members in swing districts. Pushing too hard for wall funding to be part of the next spending bill could be a problem when the government runs out of money at the end of the fiscal year. Democrats aren't expected to go along with border wall funding if Trump pushes for it, which could lead to a showdown and a potential government shutdown if it can't be resolved.

Read More