Prince Louis' christening: inside the royal baptism at St James' Palace

Prince Louis of Cambridge has been christened at St James's Palace in London.

The third child of the Duke and Duchess of Cambridge was baptised inside the Chapel Royal, where his older brother Prince George was christened in 2013, on Monday 9 July.

The occasion marked the first time Prince Louis, who is fifth in line to the British throne, has been seen in public since he left the Lindo Wing of St Mary's Hospital with his parents in April.

It was also the first time the Duke and Duchess of Cambridge appeared in public with all three of their children, as a family of five.

The family greeted Archbishop of Canterbury Justin Welby as they entered the chapel.

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According to Hello! royal correspondent Emily Nash, mum of three Catherine was overheard saying Louis reminded her "so much of George", as she cradled the sleeping bub in her arms. 

As she did for the christenings of Prince George and Princess Charlotte, the Duchess wore an outfit by British fashion house Alexander McQueen.

The prince's six godparents were among the first guests to arrive ahead of the ceremony, along with Catherine's parents, Carole and Michael Middleton, and her siblings Pippa and James.

Ahead of the ceremony, Buckingham Palace confirmed Queen Elizabeth II and Prince Philip would not be attending the event, confirming the decision was not health-related.