Ahead of a looming intraparty fight, House Speaker Paul Ryan on Thursday insisted the United States will raise the debt ceiling to avoid a default.

"We will pay our debts and we will make the debt limit," the Wisconsin Republican told CNBC from a Boeing factory in Washington state, where he was promoting tax reform.

"I'm really not worried about getting this done because I know we will get this done and we will pass the increase before we hit the debt limit," he added.

The U.S. government needs to increase its borrowing limit before the end of September or risk defaulting on its debt. Ryan's comments echoed Senate Majority Leader Mitch McConnell, who on Monday said "there is zero chance" that the U.S. will fail to raise the debt ceiling.

Treasury Secretary Steven Mnuchin has called for a "clean" debt ceiling increase, meaning the vote is not attached to other provisions. Some conservatives have opposed a clean hike, particularly during the Obama administration, seeking spending cuts, as well.

Asked specifically about a clean hike, Ryan said there are "a bunch of different options in front of us." Later Thursday, White House press secretary Sarah Huckabee Sanders said it falls on Congress to raise the debt ceiling and that the administration supports a clean increase.

President Donald Trump on Thursday appeared to partly blame Ryan and McConnell for what he called a "mess" in reaching a debt ceiling deal. Trump said he wanted to tie the debt ceiling to a bill related to the Department of Veterans Affairs that easily passed.

Trump: I requested that Mitch M & Paul R tie the Debt Ceiling legislation into the popular V.A. Bill (which just passed) for easy approval. They...

Trump: ...didn't do it so now we have a big deal with Dems holding them up (as usual) on Debt Ceiling approval. Could have been so easy-now a mess!

Ryan said GOP leaders "were looking at" that option but decided against it. He added that he did not feel targeted by Trump's tweet.

"I don't really take it as going after me," he said.

Ryan is making a series of appearances to support a tax overhaul, which he believes Congress can pass this year. Congressional leaders want to start moving legislation next month, but they also face deadlines for raising the debt ceiling and funding the government when they return from recess.

Trump's recent actions — hitting Ryan, McConnell and GOP senators and threatening a government shutdown over funding for his proposed border wall — potentially complicate the Republican agenda when lawmakers return to Washington.

Ryan anticipates that Congress will have to pass a short-term funding measure before the Sept. 30 deadline, partly because the Senate faces obligations to confirm federal officials when it returns.

The House speaker insisted that Republicans have enough time to pass a tax reform package in 2017.

"We're totally on the same page on this," he said of the two chambers of Congress and the White House.

Ryan did not go into much more detail on the tax plan than he has previously. He said he wants to keep, but potentially modernize, the mortgage interest deduction.

He added that he feels that Senate can get some Democrats behind the tax reform plan, specifically citing the states of North Dakota, Indiana and Missouri. Sens. Heidi Heitkamp, D-N.D., Joe Donnelly, D-Ind., and Claire McCaskill, D-Mo., are all up for re-election next year in states that Trump won in 2016.