Sen. Tim Kaine Timothy (Tim) Michael KaineBiden promises Democratic senators help in battleground states Second GOP senator to quarantine after exposure to coronavirus The Hill's Morning Report - Sponsored by The Air Line Pilots Association - Pence lauds Harris as 'experienced debater'; Trump, Biden diverge over debate prep MORE (D-Va.) on Sunday called on lawmakers to reopen the government, but said Democrats don't want to "waste taxpayer money" on a border wall, calling the idea — one of President Trump Donald John TrumpHR McMaster says president's policy to withdraw troops from Afghanistan is 'unwise' Cast of 'Parks and Rec' reunite for virtual town hall to address Wisconsin voters Biden says Trump should step down over coronavirus response MORE's signature campaign promises — a "vanity project."

Kaine added during an interview on NBC's "Meet the Press" that Democrats "have always been willing to invest in border security" but said those funds should be "spent the right way."

ADVERTISEMENT

"What we don't want to do is waste taxpayer money on a vanity project that's ineffective, that the president said Mexico would pay for. But spending massive amounts on border security to keep us safe, Dems do it over and over again, and it's been Republicans that have been blocking it," he continued.

Trump's demand for a wall to be built along the southern border is at the center of the ongoing partial government shutdown, which is now in its fourth week.

The shutdown, which began Dec. 22, was prompted because Trump refused to sign legislation to fund the government that didn't include at least $5 billion in funding for the wall.

Democrats in Congress have vowed not to approve any funding for a wall and have noted that Trump said while campaigning for president that Mexico would pay for the wall.

Trump has threatened to declare a national emergency to begin construction of the wall, though he has acknowledged that such a move would likely be met with an immediate legal challenge.