The pilot of a small plane put US President Joe Biden's bodyguards on alert on Saturday.

As the machine entered the protected airspace above the President's beach house in Rehoboth Beach, Delaware, Biden and his wife Jill were briefly taken to a safe location, the White House said.

"The President and First Lady are safe and there has been no attack," it said.

Biden and the First Lady later returned to their residence.

The Secret Service, which is responsible for protecting the president, said the plane had mistakenly entered the restricted airspace above the house and was "immediately escorted out".

Accordingly, the pilot had not used the correct radio channel and had not observed "the published flight instructions".