U.S. President Trump announced in the White House that Boeing has won a contract to develop the US Air Force's most sophisticated fighter jet yet.

Axar.az reports via Sky News, the new sixth-generation jet would be named F-47, Mr Trump said.

"Nothing in the world comes close to it... it's something the likes of which nobody has seen before," he added.

"(The F-47) will be the most lethal aircraft ever built."

The plane's design remains a closely-held secret, but would likely include stealth, advanced sensors, and cutting-edge engines.

The initial contract to proceed with production on the jets is worth an estimated $20bn.

Mr Trump said the jets will be built over several years and "it's something nobody has ever seen before".

"Our allies are calling constantly," Trump said, adding foreign sales could be an option. "They want to buy them also."