The Biden administration is in talks with Vietnam over an agreement for the largest arms transfer in history between the ex-Cold War adversaries, according to two people familiar with a deal that could irk China and sideline Russia.

A package, which could come together within the next year, could consummate the newly upgraded partnership between Washington and Hanoi with the sale of a fleet of American F-16 fighter jets as the Southeast Asian nation faces tensions with Beijing in the disputed South China Sea, one of the people said.

The deal is still in its early stages, with exact terms yet to be worked out, and may not come together. But it was a key topic of Vietnamese-U.S. official talks in Hanoi, New York and Washington over the past month.