The Republican chairman of the House Armed Services Committee batted down reports Wednesday that Congress is angling toward a $15 billion hike in defense spending this year.

Rep. Mac Thornberry, R-Texas, said no figure was decided yet but acknowledged any boost is likely to be less than the $30 billion requested by President Trump.

The requested funding could be paid on top of the annual defense budget and was aimed at bolstering military readiness as well as buying more F-35 joint strike fighters, F/A-18 Super Hornets and H-60 Black Hawk helicopters this year. Trump also wanted funding included for his Mexico border wall.

Leadership and appropriators are now hammering out a final spending compromise to keep the government funded through September and could include the supplemental military money along with it. Democrats had initially agreed to a $15 billion supplemental in exchange for Obamacare insurance subsidies, the Hill reported Tuesday.

"My understanding is negotiations are still going on, so there is no final number or final answer until everything is locked down," Thornberry said.

Thornberry and his counterpart, Sen. John McCain, R-Ariz., chairman of the Senate Armed Services Committee, have been pressing for big increases in defense spending, which includes a supplemental hike and a $640 billion defense budget for 2018 — $37 billion above Trump's proposal.

"My guess is the supplemental will end up being less than the president asked for, which will put more pressure on the '18 bill to make up some of the lost ground," Thornberry said.

However, the chairman declined to say what dollar amount he expects in a supplemental. "You always be careful when you draw red lines with things," he said.

His committee had wanted $18 billion in additional spending including in its annual defense authorization bill passed in December.