LONDON — Queen Elizabeth II Tuesday became the first British monarch to attend a Cabinet meeting since George III in 1781 as part of celebrations to mark her 60 years on the throne.

The queen, 86, was greeted by Prime Minister David Cameron at his Downing Street residence in London and introduced to Cabinet ministers from the ruling coalition of Conservatives and Liberal Democrats, who bowed as a mark of respect.

She wore a royal-blue wool shantung dress with matching coat by designer Stewart Parvin, and a sapphire and diamond brooch.

In the Cabinet room, she sat between Cameron and Foreign Secretary William Hague as Chief Whip George Young, who steers legislation through Parliament, updated colleagues on the passage of current bills.

Television cameras cut away as Chancellor of the Exchequer George Osborne was due to talk about the economy.

“The prime minister opened by welcoming Her Majesty to the Cabinet,” Cameron’s spokesman, Jean-Christophe Gray, told reporters in London. “The last sovereign to attend Cabinet was George III in 1781. The prime minister was able to inform Cabinet that Anglo-U.S. relations had improved markedly since then.”

Cameron’s office said yesterday that Queen Victoria, who ruled from 1837 to 1901, had also attended Cabinet. Today, Gray said further research had revealed this was not the case.

“The general event was very good-natured,” Gray said. On leaving, “she wished them all a very happy Christmas,” he said.

‘Observer Role’

“It’s an observer role,” Gus O’Donnell, the former head of the civil service, told BBC Radio 4’s “Today” program. “I’m sure Cabinet want to do this because they want to say thank you. I’ve always viewed the queen as the ultimate public servant. You think what she’s done during the jubilee period, and they just want to say thank you.”

After attending part of the meeting, the queen walked with Hague to the Foreign Office, which is adjacent to Downing Street, which houses the office and residence of the prime minister.

Hague later announced that the southern part of the British Antarctic Territory had been named “Queen Elizabeth Land” in honor of her Diamond Jubilee.

The area, which was previously unnamed, occupies about 169,000 square miles (437,000 square kilometers), making up just under a third of the whole land mass of the British Antarctic Territory, the Foreign Office said in an e-mailed statement.

That’s almost twice the size of Britain, which stands at 94,000 square miles.

Cabinet Gift

Cameron’s ministerial team presented the queen with a gift of 60 placemats paid for from their own contributions.

Made by Lady Clare Ltd., the mats feature images of Buckingham Palace, the queen’s London residence, selected from the royal library. The Cabinet also gave a donation to the Queen Elizabeth Diamond Jubilee Trust charity.

Britain staged four days of events in June to mark her jubilee. Only Victoria spent longer on the throne.

As head of state, the queen “has to remain strictly neutral with respect to political matters, unable to vote or stand for election,” according to the monarchy’s website.