LONDON: King Charles drew on his mother's inspiration on Monday as he celebrated his first Commonwealth Day as symbolic head of the grouping with a service at London's Westminster Abbey, joined by other senior members of the British royal family.

Charles succeeded his mother Queen Elizabeth as the head of the club of 56 countries that evolved from the British Empire after she died last September aged 96.

"I draw great strength from her example, together with all that I have learnt from the extraordinary people I have met, throughout the Commonwealth, over so many years," he told the congregation. "The Commonwealth has been a constant in my own life, and yet its diversity continues to amaze and inspire me."

The 74-year-old king was joined for the service by his wife Camilla, the Queen Consort, and his eldest son Prince William and his wife Kate.

He was greeted with a traditional Maori welcome outside the Abbey and also by a noisy protest from a small number of republicans who have vowed to make their views known at engagements ahead of his coronation in May.

The Commonwealth, one of the world's biggest international organisations, was always very close to Elizabeth's heart and some commentators say that helping to maintain and enlarge it was one of the biggest successes of her 70-year reign.

"Her late majesty loved the Commonwealth, and the Commonwealth loved her," said Commonwealth Secretary General Patricia Scotland.

"In our sadness at her passing, our admiration for all that she was, and our enduring gratitude for all that she gave us, we can all take heart from the fact that her vision for the Commonwealth, as an equal partnership of nations and races, has come to fruition."