Reporters grilled Sarah Huckabee Sanders about Trump's threat to shut down the government over the border wall during her first press conference in 3 weeks

White House press secretary Sarah Huckabee Sanders on Thursday repeatedly dodged questions over President Donald Trump's threat to shut down the government over funding for a wall along the southern US border.

Though Trump often promised that Mexico would pay for the southern border wall, he has since turned his attention to the Republican-controlled Congress to fund the project, which Democrats contend would cost $70 billion to build and $150 million a year to maintain.

At a rally in Arizona on Tuesday, President Donald Trump said, "If we have to close down our government, we're building that wall."

During her first press conference in three weeks, Sanders refused to answer four separate questions about whether Trump would refuse to sign a bill funding the federal government if funding for the border wall was not included.

"The president promised over and over again during the campaign that Mexico would pay for the wall. Why is he now threatening a government shutdown if congress won't pay for it?" ABC News' Jon Karl asked.

Sanders was unclear in her response.

"The president is committed to making sure this gets done," she said."We know that the wall and other security measures at the border work, we've seen that take place over the last decade and we're committed to making sure that the American people are protected."

Sanders praised job-creation statistics during the Trump administration when American Urban Radio Networks' April Ryan asked how the administration felt about federal workers possibly going without paychecks if the government was shut down, and dodged another question when pressed on the subject again.

"How is that not a concession from this White House that Mexico is not going to pay for this wall and taxpayers will?" ABC News' Cecilia Vega asked minutes later.

Sanders responded, "This is something the president is committed to he's committed to protecting American lives and doing that through the border wall is something that's important, it's a priority and we're moving forward with it."

"But he's not saying that Mexico is going to pay for it," Vega said.

"He hasn't said they're not either," Sanders replied, and when a reporter pointed out that Mexican President Enrique Pena Nieto refused to pay for the wall, she added, "Thank you, I think we've had enough outbursts in the past."

When Congress reconvenes in September, it must pass a funding bill by the end of the month in order to avoid a shutdown. Many Republican leaders like House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell have said that avoiding a government shutdown is a top priority.

Republicans need 60 votes to pass a bill continuing to fund the government, and Democrats have universally said that they would oppose a bill with funding for Trump's proposed wall.