Senate Majority Leader Mitch McConnell opened the 2018 Senate session with a statement that sets up a clash with Democrats on spending legislation that must pass in mere weeks.

McConnell, R-Ky., said the fiscal 2018 government funding bill should add extra money for military spending, which he said has been “stretched thin” under federally mandated spending reductions, beyond any cuts suffered by domestic budgets.

McConnell said the additional defense spending should not be automatically matched by a domestic funding increase, which Democrats are demanding.

“We need to set aside the arbitrary notion that new defense spending be matched equally by new non-defense spending,” McConnell said. “There is no reason why funding for our national security and our service members should be limited by an arbitrary political formula that bears no relationship to actual need.”

McConnell said defense spending cuts have outpaced domestic spending reductions by $85 billion since 2013.

Defense hawks in both the House and Senate have pushed for a boost in funding for the military which has been stretched thin by overseas conflicts and afflicted by broken down equipment, poor training, and a recent string of Naval accidents.

But Democrats are unlikely to agree to such a deal.

Most bipartisan budget agreements in recent years have required, for the most part, equal spending on domestic and military budgets in order to win the approval of Democrats.

In the Senate, where Republicans hold a mere one seat majority, at least nine Democrats will be needed to pass the spending measure.

“It has to be decided by 60 votes,” Senate Minority Whip Dick Durbin, D-Ill., said Wednesday. “Do the math.”

In a letter sent to House Democrats on Tuesday, House Minority Leader Nancy Pelosi said she and Senate Minority Leader Chuck Schumer, D-N.Y., “would continue to insist” on parity between defense and domestic spending in the fiscal 2018 budget agreement.

Lawmakers have about two weeks to reach a deal.

A short-term funding extension expires on Jan. 19.

The House and Senate leaders in both parties are expected to talk about the funding measure Wednesday afternoon at a meeting with President Trump.