Natalia Vodianova is pregnant.

The Russian model - who has children Lucas, 11, Neva, seven and Viktor, six, with her ex-husband Justin Portman - has revealed that she and her boyfriend Antoine Arnault will be welcoming their first child together in May 2014.

Antoine - the son of LVMH chairman Bernard Arnault and CEO of luxury brand Berluti - posted on Facebook: ''Hi everyone, big news today! Giving a little brother or sister to Natalia's three wonderful children is something we wanted so much: and now it's happening!

''We're going to have our first baby next year!!! Number four for her but number one for me... I'm a little stressed! She was tired the first three months but is fine now. (sic)''

Arnault is hoping their child will inherit the supermodel's looks and share his sense of humour.

He joked: ''I hope he or she gets mummy's looks (and beautiful hear) and daddy's sense of humour!!! Pleaaaaase not the other way around! (sic)''

Natalia revealed she has been ''eating all the time'' during her pregnancy and is hoping this news will help her friends understand why she has cancelled some recent plans.

She wrote: ''Please read cute post by future daddy and share our big news.

''This will explain to many of my friends and colleagues why I have been cancelling on them so often recently.

''One guy (it had to be a guy) who drives me sometimes said back in September to my assistant that I am having a nervous breakdown because I am eating all the time in the car! (sic)''