They both had huge grins on their faces," the onlooker added.
Ora, who was recently hospitalised due to exhaustion, and Hamilton flew back to Britain earlier this week on the race driver's private jet.
He won the World Championship the following season in dramatic fashion, becoming the then-youngest Formula One World Champion in history before Sebastian Vettel broke the record two years later.
Following his second world title in 2014, he was named BBC Sports Personality of the Year.
An onlooker told the tabloids, “They looked very cosy and flirty.
But a spokesperson has denied the couple are dating telling Mail Online: ‘Lewis and Winnie are just friends.’ Mmm, that old chestnut, eh?They stayed at Ora's family home on the River Bojana, with the singer's father, sister, and cousin also on vacation there.The pair flew off to Rita’s holiday home in Montenegro and got seriously flirty by the water… Rita Ora and Lewis Hamilton have been spotted getting close on holiday in Montenegro.MBE (born 7 January 1985) is a British Formula One racing driver from England, currently racing for the Mercedes AMG Petronas team.A three-time Formula One World Champion, he is regarded by fellow and former drivers as one of the greatest Formula One drivers in the history of the sport.