Britain's Queen Elizabeth will attend a Remembrance Day Service on Sunday, Buckingham Palace said, in her first public engagement in person since she spent a night in hospital last month and was subsequently advised to rest.

Last month the 95-year-old queen spent a night in hospital for the first time in years for what the palace called "preliminary investigations" into an unspecified ailment.

She has been subsequently advised to rest, and has been undertaking light duties over the last few weeks including hosting some virtual audiences.

"The Queen will attend the annual Remembrance Day Service at the Cenotaph on Sunday 14th November," Buckingham Palace said in a statement on Thursday about the ceremony to remember those killed and wounded in conflict.

"Mindful of her doctors' recent advice, The Queen has decided not to attend the General Synod Service and Opening Session on Tuesday 16th November."

Elizabeth, who is queen of 15 other realms including Australia, Canada and New Zealand and next year celebrates 70 years on the throne, is known for her robust health.

The queen, who has regularly carried out official public duties despite her age, has pulled out of events including the COP26 climate summit and a visit to Northern Ireland as a precaution following the ailment, which is not COVID-19 related.

However, the palace said that the world's oldest and longest-reigning monarch had a "firm intention" to be present at the main national service of remembrance for veterans.

Heir to the throne Prince Charles said of the queen that "she's all right" when asked how his mother was by a well-wisher during a visit in south London on Thursday.