Beyonce Knowles is celebrating her 30th birthday with close friend Gwyneth Paltrow.

The 'Single Ladies (Put A Ring On It)' hitmaker - who reached the landmark date yesterday (04.09.11) - invited the Oscar-winning actress on to the luxury yacht she is currently staying on with husband Jay Z in Venice, Italy.

Prior to welcoming Gwyneth, who is in the Italian city promoting her new movie 'Contagion' alongside Matt Damon, on board the vessel, Beyonce - who is pregnant with her first child - was spotted soaking up the sun on the top deck of the boat.

Earlier this year, Beyonce spoke of her desire to settle down into being a wife and mother.

She said: "When you're young - 18 or 19 - you have the energy and drive. That's the time to work as hard as you can.

"Now I'm a woman, and because I gave it my all, I can focus on my marriage. I can decide I want to have kids. I can be the mother I want to be and dedicate myself to my children."