Peter Phillips has introduced his new girlfriend to his grandmother, Queen Elizabeth

A source told The Sun newspaper: "The Queen is one of the most important people in Peter's life so it's only right that he introduces Lindsay to her. It was a very warm meeting and the Queen was clearly delighted to meet someone who makes Peter so happy.

Peter wanted his grandmother to see that he was "happy" with Lindsay - who was a school friend of her younger sister, Zara Tindall - and he was relieved she was "welcomed" into the fold.

The insider said: "It may still be early days but Peter wanted his grandmother to see he was happy. It is a clear sign that Lindsay has now been firmly welcomed into The Firm and a major first step if they were to ever choose to get married. The Queen just wants Peter to be happy."

Peter has daughters Savannah, 11, and Isla, nine, with his ex-wife and although he has a new partner now, relations between himself and Autumn are said to still be "incredibly warm".

The source continued: "Despite the fact that he divorced Autumn, they have two children together and relations are still incredibly warm between them. They are both moving on with their lives and accept that the other will find someone else romantically."

This is not the first time Lindsay attended a family event with her partner as in November, she escorted him to the christening service for Lucas Tindall and August Brooksbank, the sons of Zara and her husband Mike Tindall and Princess Eugenie and her husband Jack Brooksbank.