The co-leaders of the Scottish Greens have confirmed they will not attend a service of thanksgiving for King Charles in Edinburgh this week.
Patrick Harvie and Lorna Slater are both outspoken republican MSPs as well as government ministers.
Mr Harvie will instead speak at a rally outside Holyrood organised by the anti-monarchy group Our Republic.
Scottish Conservative MSP Donald Cameron said the decision was “akin to student politics”.
During a national service of thanksgiving, the King will be presented with the Scottish crown jewels in a ceremony in Edinburgh on Wednesday, marking his Coronation.
Last year, members of the Scottish Greens boycotted a debate at Holyrood at which MSPs congratulated the Queen on her platinum jubilee.
At the time the party, which is part of a Scottish government power sharing deal, said a head of state should be chosen by and be accountable to voters.
Confirming her intention not to attend Wednesday’s ceremony, Ms Slater said: “In 21st Century Scotland, the monarchy is nothing to celebrate.”
She added: “It is an out-of-date and undemocratic institution.
“How can we justify a system that allows one family to enjoy so much unearned wealth and privilege at a time when millions of people have so little?”
Mr Harvie added that the monarchy was one of the reasons why he supported Scottish independence.
He said: “There are many people in Scotland who regard the monarchy as a tiresome spectacle and a symbol of values we don’t hold.”
“I will be proud to speak at the Our Republic rally and to stand with others who want to build a more democratic society where power and wealth belongs to the people rather than being passed down as an inheritance.”
Donald Cameron said Mr Harvie’s choice to speak at the rally instead was “predictably infantile”.
He added: “If he wants to ask big questions, he should start with how he conducts himself as a government minister.
“The Greens may have failed to deliver a deposit return scheme, but they can definitely recycle tedious anti-monarchy rants.
“As on so many issues, the extremist Greens are out of touch with the majority of Scots, who see the coronation and the King’s commitment to Scotland as something to celebrate.”