PLAID Cymru AM Leanne Wood confirmed last night that she will be boycotting the Queen's official opening of the new Assembly building on St David's Day.
Ms Wood, a fervent republican, said her conscience would not allow her to attend the ceremony. She also refused to attend the royal opening in 2003, immediately after she was elected as a regional list AM for South Wales Central.
She told the Western Mail, "When we campaigned for the Assembly originally, we wanted to do things differently in Wales from the way they had previously been done in Westminster.
"I am not at all happy about the fact that after I was elected, I had to swear an oath of allegiance to the Queen before I could represent my constituents. In effect, I had to lie. Plaid Cymru has put down an amendment to the current Government of Wales Bill, calling for the oath of allegiance to be changed so that AMs pledge to serve the people instead of the monarch.
"As a republican, I just wouldn't feel right attending an Assembly meeting presided over by an unelected head of state. I know that most other Plaid AMs are also republicans, although they will not be joining my boycott.
"Dafydd El [Plaid AM Lord Elis-Thomas, the Presiding Officer] argues that if anyone other than the head of state opens the Assembly, the institution is devalued. I can see the argument, but for me it's important to make a point and keep alive the debate over whether it's appropriate to have an unelected head of state.
"I'm aware that while there are people on both sides of the debate who are passionate one way or the other, most people these days don't really care about the issue. My position is that I don't want to just go along with the adoring masses.
"I don't know how long it will take before we get to a situation where there is an elected head of state - I don't see any imminent change based on the reaction to my 'Mrs Windsor' comment in 2004.
"But I'm encouraged that those who contacted me to support me were nearly all young people. Support for the monarchy seems to be a generational thing, maybe something to do with the war."
In December 2004, during a debate on the Queen's Speech at Westminster, Ms Wood referred to the monarch as Mrs Windsor. After refusing to withdraw the reference, she was asked by the Presiding Officer to leave the chamber for the rest of the day.
At the time, Labour AM Leighton Andrews said, "It is offensive and unacceptable for Leanne Wood to abuse the privilege of being able to contribute in a debate on the Queen's Speech in Wales' National Assembly to take a cheap shot at our monarch."
He went on to describe her comments as "more suited to a students' union than Wales' national forum for debate".
Last night the Assembly's Conservative leader Nick Bourne said, "It's rather disappointing that Leanne Wood will not be present at such an important event for Wales. Other Plaid Cymru members will be attending who don't believe Wales should be part of the UK either.
"It's a shame Leanne will not be there, but one has to say she has been consistent in her approach."
Plaid Cymru president Dafydd Iwan said, "I've managed to stay away from such occasions myself, which may be part of the reason I haven't tried very hard to become a member.
"I have respect for people like Leanne who have the courage of their convictions and stay away.
"Decisions like this are sometimes difficult. I think it's important not to compromise to such an extent that you have a fuzzy sense of your own principles," he added.
"This isn't something there should be a party line on. It's for individuals to make up their own minds."