A registrar says he refuses to conduct new ceremonies for immigrants granted British citizenship on moral grounds.
Mr Roney says people "should not be forced into" the ceremonies
David Roney, a deputy superintendent registrar in Rochdale, says immigrants should "not be forced into" taking part in the ceremonies against their will.
He said he will not carry out the "totally unnecessary" ceremonies.
Mr Roney was speaking before the first citizenship ceremony, attended by Prince Charles and home secretary David Blunkett took place in Brent, London.
Oath of allegiance
All applicants successfully applying for citizenship since 1 January 2004 will now take part in the ceremonies, where new citizens swear an oath of allegiance to the Queen and give a pledge to uphold British democratic values.
Mr Roney told BBC Radio Five Live: "I think it's totally wrong to force people that want to come and live and work in this country to force them into a ceremony that they probably don't believe in.
"How many people in this country would be willing to take an oath of allegiance to the Queen? I certainly wouldn't."
He said people coming to live and work in the UK "don't need to become royalists immediately" and that they "may well disagree with the royal family".
He said: "I won't do it. I joined this job in 1995 to marry people - it's a lovely job, but this was never in my job description.
"As far as I know my contract of employment has not changed and I will not do these ceremonies.
But Karen Knapton, honorary general secretary of the Society of Registration Officers, said Mr Roney would have to perform the "statutory duty" of conducting a ceremony if asked, or face losing his job.
She told BBC News Online: "As registration officers we can't let personal feelings interfere - we have to carry out our duties regardless.
"There may well be other thing that come in that we feel we can't do but as statutory officers we have to do them.
She said the society broadly welcomed the ceremonies although there were concerns about registrars being able to fit them into their schedules.
A spokesman for Rochdale Council said Mr Roney's opposition to the ceremonies was "his personal view and does not represent the position" of the council.
He said Mr Roney, a part-time registrar, would probably not be asked to conduct any ceremonies because the council was asking only full-time staff to do them.
He told News Online: "Our part-time deputy superintendent registrars are not being asked to conduct citizenship ceremonies, although legally it is part of their duties and if necessary they could be required to do so."