WASHINGTON • An 11-year-old boy has earned a "great job" and a high five from President Donald Trump for mowing the White House lawn.

Frank Giaccio from Falls Church, Virginia, wrote to the US President earlier this year, saying he had his own lawn mowing business and that it would be an "honour" to offer his skills.

The White House accepted his offer and Frank was invited to mow the grass in the Rose Garden on Friday under the watchful eye of uniformed park service workers.

Wearing goggles and work gloves, the young entrepreneur started work at around 9.30am. Mr Trump appeared about 10 minutes later, gave Frank a high five and told him he was doing a "great job".

"That's the real future of the country right there - we're lucky," the President said. "Maybe he'll be president some day."

In an interview with Fox Business before heading to the White House, Frank said the day was shaping up to be "pretty much the best day of my life". On Friday, Frank's father, Mr Greg Giaccio, said his son was not immediately available to comment because he was awaiting a tour of the White House.

Mr Giaccio said it just made sense for Frank to reach out to high-profile customers.

"You have this image that (presidents) are intimately involved with everything," Mr Giaccio said. "He started a business - obviously, Mr Trump is in the news all the time. He said, 'Maybe I'll write him'."

Frank is not the only letter writer in the family. "One of my younger kids wants to write (to) Nasa (National Aeronautics and Space Administration) to get a trip to the moon," Mr Giaccio said.

Frank had also written to then President Barack Obama, but only got a form letter in response.

AGENCE FRANCE-PRESSE, WASHINGTON POST