(Reuters) -Outgoing U.S. Defense Secretary Lloyd Austin has recommended a boost in defense spending by about $50 billion more than the current 2026 projections, a move that could push the defense budget beyond $1 trillion in the coming years, Bloomberg News reported on Monday.

In a Nov. 27 letter to the Office of Management and Budget that was seen by Bloomberg, Austin recommended leaving President-elect Trump's incoming administration a proposed five-year defense plan that starts with $926.5 billion in fiscal 2026, compared with a projected $876.8 billion.

The Pentagon and the Office of Management and Budget did not immediately respond to a request for comment.

"I have not wavered in my assessment that meeting the demands of our strategy requires real growth" above inflation "and sustained new investments in fiscal years 2026-2030," Austin wrote in the letter, according to Bloomberg.

President Joe Biden's 2025 defense and national security budget request released in March last year, was just 1% higher than the previous year, owing to a two-year budget deal struck in mid-2023 that limited the budget to a 1% increase.

The move forced a slowdown in spending on a wide range of programs and delayed efforts to rebuild weapons stocks depleted by wars in Ukraine and Israel.

The letter also proposed spending of $972.8 billion in the fiscal year 2027, and more than $1 trillion in the fiscal year 2028, the Bloomberg report said, adding that the spending would extend beyond $1 trillion in fiscal years 2029 and 2030.

Austin's proposed funding, however, does not include assistance to Israel and Ukraine, but is limited to the Pentagon, according to the report.

There was no immediate clarity on whether Trump would take up the idea proposed by Austin.

The U.S. president-elect had declared last week that members of the NATO military alliance should spend 5% of gross domestic product (GDP) on defense - a huge increase from the current 2% goal.

(Reporting by Chandni Shah in Bengaluru; Editing by Kim Coghill and Lincoln Feast.)