"I've said 100 times we're going to be able work with whoever our nominee is, we're going to be able to present a unified front. That's my anticipation -- whoever the nominee is going to be," Ryan told reporters at his weekly press conference on Capitol Hill.
He also repeated his policy of not commenting on "what's up and what's down in the day to day presidential election contest."
"That primary is well on its way, it's got a long way to go, but we're going to be able to work with whoever our nominee is," Ryan said.
The speaker stressed that he and House Republicans would continue to craft a policy agenda for the Republican presidential candidate to pick up once the primary process was over.
But it's unclear whether Trump would even listen to any detailed platform from the House GOP members.
Ryan has a long history of promoting free trade, and Trump has railed on the latest Trans-Pacific Partnership agreement. Trump also recently blamed Ryan, who was the GOP's 2012 vice presidential nominee, for the party's loss in that election because of his proposals to overhaul Medicare.
Pressed again about Trump's philosophical differences with his own positions, Ryan again stayed on message.
"We'll cross these bridges when we get to it but I do believe we will be able to unify as a party and I believe that whoever our nominee we'll be able to find a way to make a unified front work," he said.
"By the way Congress will have its own ideas so that's what we do. We're Republicans, we all have individual ideas and we all gravitate from the same principles an we'll be applying those principles and offering people a choice," Ryan added.
As House speaker, Ryan will preside over the Republican National Convention in July in Cleveland. He told reporters he hasn't been studying up on delegate math and convention rules, downplaying his role as "ceremonial."