London: The Duchess of Cambridge has been taken to hospital in the early stages of labour, Kensington Palace has said.

She travelled by car from the palace to St Marys in Paddington, west London, with her husband the Duke of Cambridge.

The couple do not know the sex of their first child, who will be third in line to the throne.”Things are progressing as normal”, said a spokesman. The next official announcement is likely to be that of the birth.

The worlds press have been camped outside St Marys for days in anticipation of the birth. The due date had never been officially announced but had widely been expected to be mid-July.

Royal vehicles were seen at a back entrance to the hospital at about 06:00 BST, with the announcement coming from Kensington Palace an hour-and-a-half later.

The couple, both 31, travelled to the hospital without a police escort, their spokesman said.

The duchess is being tended by a top medical team led by the Queens former gynaecologist Marcus Setchell, who delivered the Countess of Wessexs two children.

She will give birth in the hospitals private Lindo wing, where Prince William and his younger brother Prince Harry were born.

There is a strong police presence around the hospital and two police officers are guarding the entrance to the private wing. The media scrum parked outside is having to contend with the heat on what is expected to be the hottest day of the year