Simon Cowell is rumoured to be converting to Judaism for Lauren Silverman.

The 'X Factor' boss - who was raised a Roman Catholic - pledged a whopping £100,000 in support of the Israeli army at a plush gala for the Friends of the Israel Defence Forces, sparking speculation the music mogul could be changing his religion for his pregnant girlfriend.

A source told the Daily Mirror newspaper: ''Simon is getting increasingly excited about becoming a daddy. He really is embracing fatherhood and wants to be the first person to cradle his newborn son.

''He is open to reason on the subject of religion and the faith in which his son is brought up. But he is naturally inquisitive and really wants to visit Israel so that he can make a more informed decision.''

Although the 54-year-old star has expressed little interest in religion in the past, his late father, Eric, was Jewish, and Simon is thought to want a traditional Jewish ceremony if he ends up getting married to Lauren after their son is born next year.

Meanwhile, Lauren is expected to give birth to Simon's first child in New York City on February 28 after it emerged the pair have reportedly already booked a delivery room in one of the most exclusive hospitals on the east coast of the US.