At its peak, 13.4 million watched on the main BBC One channel, with an average of 11.9 million watching Saturday’s coverage of the ceremony.

A signed version on BBC Two peaked at 1.7 million, averaging at 1.4 million, a statement from the public broadcaster read.

Saturday’s coronation — the first to be held in Britain in 70 years — was only the second to be televised, and the first to be shown in colour.

But the figures indicate that overall viewing figures were well down on previous major royal occasions.

Last year’s state funeral of Charles’s mother Queen Elizabeth II attracted one of the biggest television audiences in the UK in modern times.

An estimated average audience of 26.2 million watched on TV sets alone, peaking at 28 million, including 18.5 million on the BBC.

In 2011, more than 24 million viewers watched the wedding of Charles’s son Prince William on BBC terrestrial television.

In 1997, more than 32 million viewers in the UK watched the funeral of Charles’s first wife and William’s mother, Princess Diana.

The 1953 coronation of Elizabeth is seen as a breakthrough in broadcasting, as it was the first shown on TV.

Then some 27 million people watched and 11 million listened to the service on the radio, according to Buckingham Palace. But TV set ownership was low.

The BBC was the only broadcaster at the time.

Since then the media landscape has been transformed, with dozens more channels, as well as online, on-demand and streaming services.

Charles’s coronation was also broadcast live by commercial channel ITV — which only launched two years after Elizabeth’s coronation — and others including Sky News.

Their viewing figures were not immediately available.