When asked earlier today how it feels to hit 40, Prince Felipe said that he feels "fit, very happy with family life and full of energy to live and work." He was speaking outside Defence headquarters where he has been holding a video conference with Spanish troops deployed on peacekeeping missions in Lebanon, Kosovo, Sarajevo and Afghanistan.

An Army and Air Force commander and Navy captain, the prince had wanted to spend his birthday with the Lebanon contingent, but adverse weather conditions forced the trip to be postponed.

Before starting the video conference, Prince Felipe admitted that the best present he has received was this morning when Princess Letizia and his daughters - the Infantas Leonor and Sofía - sang 'Happy Birthday To You' for him.

No formal event has been arranged to mark the prince's landmark, which he will be celebrating in private with the family.

The photo of Prince Felipe and his eldest daughter Leonor was taken in the gardens of the Zarzuela Palace in Madrid on the 29th November last year during the filming of a 40th birthday documentary special.