Prince William is usher at wedding of aristocrat the Duke of ...

LONDON -- LONDON (AP) — Prince William took a day out from royal duties on Friday to serve as an usher at the wedding of his friend Hugh Grosvenor, the Duke of Westminster, an event briefly disrupted by environmental protesters.

The wedding of 33-year-old Grosvenor, one of Britain's wealthiest landowners, to his partner Olivia Henson, 31, is one of the high-society events of the year in Britain.

William, 41, arrived with his fellow ushers at Chester Cathedral in northwest England ahead of the midday service. The venue is close to the duke’s 10,000-acre (4,000-hectare) Eaton Hall estate, where guests were due to attend a private wedding reception.

Hundreds of onlookers gathered outside the cathedral cheered the arrival of Grosvenor, dressed in a morning suit, and Henson, wearing a white wedding dress by British designer Emma Victoria Payne. Her long veil, worn over a tiara, rippled in the wind.

As the couple emerged from the cathedral to kiss in front of the waiting crowd, two environmental protesters sprayed orange powder from a fire extinguisher. They were quickly led away by police.

Cheshire Police said a 69-year-old woman and a 73-year-old woman were arrested on suspicion of public order offenses. The group Just Stop Oil said the two were its members, demanding an end to fossil fuel exraction.

Grosvenor is a godfather to 10-year-old Prince George, the eldest son of William and his wife Kate.

Kate, who is being treated for cancer, did not attend the wedding. Neither did William’s estranged younger brother Prince Harry, who lives in California with his wife Meghan and their two children.

Grosvenor inherited his title at the age of 25 when his father died in 2016. His ancestor, Sir Thomas Grosvenor, married heiress Mary Davies and acquired what was then marshland in 1677. Over the generations the family developed the land into two of London’s most affluent neighborhoods, Mayfair and Belgravia.

The family’s Grosvenor Estate owns 300 acres (121 hectares)of land in London, as well as land across Britain and housing, office and retail space around the world.

The 2024 Sunday Times Rich List estimated the duke’s wealth at just over 10 billion pounds ($12.8 billion.)