More than half a million people have signed a petition to have former prime minister Sir Tony Blair's knighthood "rescinded".
Sir Tony was appointed by the Queen a Knight Companion of the Most Noble Order of the Garter, the oldest and most senior British Order of Chivalry.
The Change.org petition, set up three days ago, has more than 580,000 signatures and is calling for the former Labour leader to be stripped of his appointment.
A statement accompanying the petition says it holds Sir Tony Blair "personally responsible for causing the death of countless innocent, civilian lives and servicemen in various conflicts".
"Tony Blair is the least deserving person of any public honour, particularly anything awarded by Her Majesty the Queen," the petition continues.
"We petition the Prime Minister to petition Her Majesty to have this honour removed."
Sir Tony, 68, led New Labour to a landslide victory in 1997, winning two subsequent general elections before quitting Westminster a decade later, paving the way for his chancellor Gordon Brown to take over as prime minister.
Sir Tony was prime minister during the Allied military invasions of Iraq and Afghanistan.
The former barrister became a Middle East envoy and set up his own non-for-profit group, the Tony Blair Institute for Global Change, after leaving politics.
Current Labour leader Sir Keir Starmer dismissed criticism of Sir Tony's knighthood, saying he deserves the honour.
He told ITV's Good Morning Britain: "I don't think it's thorny at all; I think he deserves the honour. Obviously, I respect the fact that people have different views.
"I understand there are strong views on the Iraq war. There were back at the time and there still are, but that does not detract from the fact that Tony Blair was a very successful prime minister of this country and made a huge difference to the lives of millions of people in this country."
Meanwhile, vaccines minister Maggie Throup also defended Sir Tony's appointment, telling LBC: "I think he did lots of good things. And I think it's only right that we do honour our previous prime ministers. And he was prime minister for such a long time."
Commons Speaker Sir Lindsay Hoyle has suggested that all former prime ministers should be offered a knighthood because "it is one of the toughest jobs in the world".
Each year, Royal Knights and Ladies of the Order of the Garter gather at St George's Chapel in Windsor for a colourful procession and ceremony.
Crowds watch as they walk down the hill to the chapel from the state apartments, dressed in blue velvet mantles, red velvet hoods, black velvet hats and white ostrich plumes.
Sir Tony, who left Downing Street more than 14 years ago, is one of three new appointments announced by the palace.
Appointments to the Garter are in the Queen's gift and made without prime ministerial advice, and are usually announced on St George's Day – April 23 – but she can do so at any time, and has chosen this one to coincide with the New Year Honours.