Miliband says son gorgeous – just like father

The boy arrived late on Sunday night, weighing 8lb 3oz.

Both mother Justine Thornton and baby are said to be doing well after the birth at University College Hospital in London.

Mr Miliband will take now take two weeks of paternity leave from Parliament.

He was at the hospital, near the couple's home in north London, when the baby arrived.

The new addition to the family has yet to be given a name.

He said: "We didn't know he would come quite as quickly as he did. Justine did absolutely brilliantly.

"He's really gorgeous, he looks a bit like me."