WASHINGTON (AP) — President Donald Trump lashed out on Thursday at Republican leaders in Congress, suggesting efforts to increase the country’s borrowing limit are “a mess!”

On Twitter, Trump says he asked Senate Majority Leader Mitch McConnell and House Speaker Paul Ryan to attach legislation to increase the country’s borrowing limit to a bill related to veterans. Trump said they didn’t do it and “now we have a big deal with Dems holding them up.”

Raising the federal borrowing limit is a must-do item for Congress when they return from summer break. The government has enough money to pay its bills until Sept. 29. After that, Congress would have to give permission for the government to borrow more money to meet its obligations.

McConnell, at an event in Louisville, Kentucky on Thursday, did not respond to questions about Trump’s comments. Ryan’s office did not immediately respond to a request for comment.

Earlier this week, McConnell appeared in Kentucky with Treasury Secretary Steven Mnuchin, saying: “There is zero chance, no chance, we won’t raise the debt ceiling.”

The federal government has never before defaulted on debt payments. Financial experts have warned that default on U.S. bond payments could roil financial markets.

The other top priority for Congress when they return to Washington is funding the government to prevent a shutdown. The government’s fiscal year ends Sept. 30 and legislation is needed to prevent a partial shutdown of federal agencies.

Trump’s long-promised wall along the U.S.-Mexican border could complicate those efforts. Trump threatened Tuesday to force a federal shutdown unless Congress provides funds for the project.

White House counselor Kellyanne Conway stressed on Thursday the president was serious about moving forward with the wall.

Speaking on “Fox and Friends”, Conway says Trump is “going to stick to building that wall and he wants the money to pay for it.” She adds: “anybody who is surprised by that has not been paying attention for two years.”

The latest Twitter outburst from the president came a day after Trump and McConnell pledged to work together, amid reports of tension.

White House press secretary Sarah Huckabee Sanders said the two “remain united on many shared priorities.”