Queen leads historic beacon lighting ceremony after pulling out of next event due to 'discomfort'

The Queen has officially touched the Commonwealth of Nations globe to begin the ceremonial beacon lighting ceremony.

After a short bugle call, Her Majesty symbolically led the lighting of the principal Jubilee beacon from Windsor Castle, as part of a special dual ceremony with Prince William.

The Duke of Cambridge was waiting 34km away at Buckingham Palace, where the beacon centrepiece was illuminated on the Queen's touch command. 

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There are over 2,500 Platinum Beacons being lit throughout the UK and the Commonwealth to mark the Queen's historic 70-year reign.

The Queen, 96, took part in the beacon ceremony after cancelling her planned attendance at the Thanksgiving Service at St Paul's Cathedral tomorrow due to "discomfort" during the Trooping The Colour parade.

"The Queen greatly enjoyed today's Birthday Parade and Flypast but did experience some discomfort," a spokesperson for Buckingham Palace said.

"Taking into account the journey and activity required to participate in tomorrow's National Service of Thanksgiving at St Paul's Cathedral, Her Majesty with great reluctance has concluded that she will not attend," the statement continued.

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"The Queen is looking forward to participating in tonight's Beacon lighting event at Windsor Castle and would like to thank all those who made today such a memorable occasion."

The Service of Thanksgiving is set to be attended by several other royals, including Prince Harry and Meghan Markle.

A royal source told People the monarch's episodic mobility issues flared up during the long parade and flypast event.

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The Queen was pictured using her cane on the palace balcony as she took the salute and watched the flypast alongside members of the royal family.

She also used her cane to approach the Commonwealth of Nations globe on Thursday evening UK time.

The lighting of the beacons is an ancient form of communication and sign of unity, and has been used to mark royal jubilees and weddings throughout history.