Sen. John McCain is calling for the end of sequestration.

McCain, R-Ariz, was joined by military experts at The Heritage Foundation Wednesday to discuss the future of the 2016 National Defense Authorization Act (NDAA), which outlines the budget expenditures for the Department of Defense.

The NDAA for fiscal year 2016 is being negotiated between the House and the Senate, and a final version is expected to pass in the next few weeks.

This authorization bill determines where military funding will be spent, but an appropriations bill must also be passed in order to authorize the government to actually spend that money.

“We need new ideas,” McCain said. “We must champion the cause of defense reform.”

McCain said sequestration must be repealed because he says it is preventing military personnel from performing at optimum capacity.

The term sequestration refers to automatic defense budget cuts.

“My friends, we can’t abide by a system that puts the men and women who are serving this nation at a greater risk,” McCain said.

The White House has threatened to veto the defense bill once it reaches the president’s desk.

The bill would authorize boosting the defense budget by adding money to a war fund that is not subject to budget caps, known as sequestration, which President Obama opposes.

McCain said he is “concerned” the president will veto the bill.

But experts think that choice would not be in the White House’s best interests.

“I think it would be a big mistake for the commander-in-chief to veto this bill,” said John Bonsell, a former minority staff director for the Senate Armed Services Committee.

Typically, the bill receives bipartisan support, although the number of amendments to this year’s bill has stimulated increased debate in the Senate.

The White House is opposed to some amendments, including those related to Guantanamo Bay and ones that would decrease federal spending.

Among Congress, the majority of the disagreements are not regarding reduced defense spending.

“This disagreement is about the non-defense part of the bill,” Todd Harrison said. “This is not about the defense budget. The fight is about non-defense.”

According to Roger Zakheim, visiting fellow at the American Enterprise Institute and former deputy staff director of the House Armed Services Committee, every year there is a “squirrel” in the NDAA bill—some unforeseen issue that suddenly arises and must be solved before the legislation is passed.

It is uncertain what the “squirrel” will be for the 2016 NDAA bill.

The legislation has been passed for 53 consecutive years. The House passed its version of the bill in May and the Senate passed its legislation in June, but the bills must now be reconciled.