President Joe Biden on Friday defended his decision to reject a plan for the U.S. to facilitate transfer of fighter jets to Ukraine.

"That's called World War III," he said, according to reporting by the New York Post.

Biden faces bipartisan criticism and pressure over his decision to nix an offer by Poland. Poland was willing to transfer 28 Soviet-designed MiG-29s.

Not much earlier, the Post said, Secretary of State Antony Blinken said Sunday that Poland had a "green light" for the move.

But Biden took the decision in an altogether different direction.

Speaking to an assemblage of House Democrats in Philadelphia, the president had this to say: "The idea that we're going to send in offensive equipment and have planes and tanks and trains going in with American pilots and American crews — just understand, don't kid yourself, no matter what y'all say, that's called World War III."

Under the terms of the Polish plan, Poland had offered to fly the jets to Ramstein Air Base in Germany, where the U.S. was to then facilitate the transfer to the Ukrainians to help them repel the two-week-old invasion of their country by Russia.

One detail that was unclear, the Post said, was whether U.S. or Ukrainian pilots would fly the planes into Ukraine.

The White House has repeatedly said it is willing to support and defend NATO allies from a potential spillover of hostilities and Russian aggression across the border. And America is also providing military arms such as hand-fired missile launchers, as well as humanitarian aid.

But Biden has said he does not want to put U.S. troops into Ukraine, lest it provoke Russian President Vladimir Putin into an expanded war, one no longer limited to Ukraine.

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