Two federal lawmakers warned Tuesday that the District needs more money for a fund that covers the unique security needs of the nation’s capital, saying it has been depleted by inadequate congressional payments and President Trump’s failure to pay back more than $7 million in inauguration costs.

Del. Eleanor Holmes Norton (D), the District’s nonvoting representative in Congress, and Sen. Chris Van Hollen (D-Md.) wrote in a letter to leaders of the House and Senate appropriations committees that the District needs a $6 million infusion to its Emergency Planning and Security Fund. The account covers the cost of protecting the city from terrorist threats and providing security at events such as protests, state funerals and the visits of foreign dignitaries.

Norton and Van Hollen said the fund is on track to run out of money as soon as next month at its current rate of spending — and that’s without accounting for expected additional costs related to Trump’s planned appearance at the Lincoln Memorial on the Fourth of July.

Without a new appropriation, they wrote, the District “would be put in the untenable position of not providing support for certain federal events or having to divert its local funds from local public safety activities.”

The Washington Post reported last week that the White House and Congress never repaid the District government $7.3 million for the president’s 2017 inauguration, which cost the city a total of $27.3 million. The city covered the shortfall by transferring money from the special security fund.

A White House official said last week that the city was given the money it originally requested and that when the inauguration expenses were higher than originally projected city officials agreed to use unspent money in the security fund.

City officials disputed that account.

Until recently, the security fund regularly carried over unused money from year to year. But federal funding for the account has lagged behind increasing costs for demonstrations and other events in the Trump era. In fiscal year 2017, $14.9 million was added to the fund while $24.4 million was spent.