A beaming Queen Elizabeth waved to cheering crowds massed outside Buckingham Palace on Thursday as Britain kicked off four days of pomp, parties and parades to celebrate her record-breaking 70 years on the British throne.
The 96-year-old monarch appeared on the balcony alongside her family, but the palace later said she had experienced a recurrence of mobility problems and some discomfort, and would no longer attend a Service of Thanksgiving on Friday.
The queen has reduced her public appearances in recent months due to "episodic mobility issues," and the palace had warned that her attendance at events to mark the Platinum Jubilee would be decided nearer to the time.