Actress jets off to Italy's Amalfi coast with the actor
The couple were seen kissing and cuddling on a boat off Italy’s Amalfi coast.
And pals say the actress, 26, who split from Rhys Ifans, 39, last month, has fallen hard for the 33-year-old billionaire.
‘Sienna is totally besotted with Balthazar,’ a source tells the Daily Mirror.
‘Their relationship has gone from strength to strength over the past month and Sienna finds him utterly irresistible.
‘Balthazar arranged for the trip to one of the most beautiful and exclusive parts of the Med.’
Sienna was introduced to US actor Balthazar by her pal Matthew Rhys, his co-star on Brothers And Sisters.