Meghan Markle joins Kate Middleton and the royal family at the Commonwealth Service: all the pictures

All eyes were on Meghan Markle as she has arrived for her first official event with the Queen at a service marking Commonwealth Day. Looking stylish as ever, the former US actress appeared to be in great spirits as she joined her fiancé Prince Harry and the Duke and Duchess of Cambridge at Westminster Abbey on Monday afternoon. Meghan's attendance at the service marks a major milestone for the bride-to-be, as it is the first time she has taken part in an official event with the Queen.

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Meghan, 36, stunned in a chic navy dress which was styled further with a white coat by Amanda Wakeley and navy high heel shoes. With her glossy brunette tresses worn in sleek waves underneath a lovely white hat by Stephen Jones, her makeup was flawlessly applied with muted tones of makeup. Meanwhile, Kate dressed her blossoming bump in a navy blue coat and dress by luxury label Beaulah London, and accessorised the outfit with a co-ordinating hat by Lock and Co. and matching blue heels.

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Celebrated across the Commonwealth, the day is an opportunity for each of the institution's 53 member states to highlight the positive values of the family of nations. Other members of the royal family at the service included, the Prince of Wales, Duchess of Cornwall, Duke of York and Princess Royal and the Prime Minister Theresa May.

The service, which is the largest annual inter-faith gathering in the UK, is held every year to celebrate the Queen's lifetime commitment to the Commonwealth as Head of its 53 countries. The theme of this year's gathering was 'Towards a Common Future' to emphasise how the Commonwealth can address global challenges and work to create a better future for its 2.4 billion citizens.

William and Kate are due to welcome their third child together next month. The expectant royal's last engagement is set to take place on 17 March, which may be her last public appearance before welcoming baby number three. Kate previously took the final month off during her pregnancies with both Prince George and Princess Charlotte.

The event at Westminster Abbey is a public acknowledgement by the Queen of the former Suits actress, who will marry Prince Harry in Windsor on 19 May.

This is the second time that Meghan has appeared in public for an official engagement with soon-to-be sister in law Duchess Kate. In February, the two ladies took part in the Royal Foundation Forum in London and co-ordinated their outfits for the occasion - they both opted for striking blue dresses that showcased their individual styles.

The Queen, who is Head of the Commonwealth, wore a plum Angela Kelly coat and hat, and matching floral dress. The coat featured a velvet collar. The monarch wore a diamond and ruby flower brooch and her trademark pearl necklace.

The Commonwealth has played an important role throughout the Queen's reign, and she takes a special interest in the family of nations. Harry and Meghan signalled their commitment to the Commonwealth and its people when they both mentioned the institution - which has the Queen as its head - during an interview to mark their engagement. The prince said they looked forward to travelling around the Commonwealth, meeting some of the 2.4 billion people from the 53 member states.

The Duchess of Cornwall looked lovely in dark blue as she arrived at the Commonwealth Day service.

Cheryl's partner, One Direction star Liam Payne performed at the service.

The Countess of Wessex also opted for a chic blue coat, which was styled with a coordinating hat and nude heels.

Meghan was later seen talking to children. One child even handed the future royal a lovely bouquet of flowers.

After the service, William, Kate, Harry and Meghan will attend a private reception for those involved in the event. The Commonwealth has played an important role throughout the Queen's reign, and she takes a special interest in the family of nations.

Organised by the Royal Commonwealth Society, the Commonwealth service is the largest annual inter-faith gathering in the UK. Other royal guests included the Duke of York, Princess Royal, the Duchess of Gloucester and Princess Alexandra.