World record holder Eliud Kipchoge will attempt to defend his London Marathon title in April with the Kenyan set to go head-to-head with Britain's Sir Mo Farah.
The Kenyan secured a third victory at last year's race, having previously triumphed in 2015 and 2016.
He missed the 2017 edition.
Kipchoge, the 2018 International Association of Athletics Federations (IAAF) Athlete of the Year, set the marathon world record in Berlin.
He achieved a time of 2 hours, 1min and 39sec at the race last year.
The Kenyan star also holds the London Marathon course record, which stands at 2:03:05.
Kipchoge will head into the race as favourite to claim victory, but could face competition from Farah.
The Briton, a four-time Olympic champion on the track, finished third in London last year, before winning his maiden marathon title at the Chicago Marathon.
"It is always a great honour to come and race the Virgin Money London Marathon and I'm excited to be returning in 2019," said Kipchoge.
"I had a memorable 2018, winning the Virgin Money London Marathon and then setting a new world record at the BMW Berlin Marathon.
"I'm hoping that 2019 is just as good to me.
"I am looking forward to racing Sir Mo Farah again.
"He is a great champion and proved in Chicago that he can win a major marathon so I relish the battle with him and also the many other great athletes that I'm sure will once again be on the start line in London."
Kipchoge and Farah currently top the Abbott World Marathon Majors leaderboard, following the opening three races of the six event series.
They both have 25 points, along with Ethiopia's Lelisa Desisa.
Victory in London could boost Kipchoge or Farah's chances of winning the series.
Ethiopia's Shura Kitata will also return to the London Marathon after finishing runner-up to Kipchoge last year.
That means the top three from the 2018 podium will all be in London again this year.
"There is no doubt that Eliud Kipchoge is the greatest marathon runner of all time," said Hugh Brasher, the London Marathon event director.
"His world record at the BMW Berlin Marathon was a legendary sporting moment and one more win at the Virgin Money London Marathon would make him the most successful athlete in the history of the elite men's race in our event's illustrious history.
"Since Sir Mo Farah won the Bank of America Chicago Marathon in October, everyone has been talking about another head-to-head between Mo and Eliud and we are absolutely thrilled that this showdown will happen at the 2019 Virgin Money London Marathon.
"We will see two absolute legends of distance running competing over 26.2 miles of roads in the greatest marathon in the world.
"I cannot wait until Sunday 28 April to see who comes out on top."