The lobby group says Chief Minister Katy Gallagher has ''disappointed'' Canberra's Christian residents by opposing the service, which was organised by Assembly Speaker Vicki Dunne.

But Ms Gallagher has accused the Canberra Liberals MLA of trying to create a religious divide among Canberrans by involving the ACL.

The Canberra Times reported last week that Mrs Dunne had organised the service, to be held at St Paul's in Manuka, and wrote to the Chief Minister asking for an Assembly committee to help plan the event.

Ms Gallagher said the government objected to the commencement service because it wanted to maintain the Assembly's neutrality on matters of religion.

While there are other jurisdictions that mark the beginning of a new parliamentary year with a church service, the ACT has no such tradition.

In a statement on the Christian lobby's website, managing director Jim Wallace said ''it was disappointing for those in the ACT who had a Christian faith that Ms Gallagher declined to attend a ceremony''.

Mr Wallace said the service ''would be important to those who believe that our society stands out as a civil one because of its Christian fundamentals, and would want to see Christ continue to bless and preserve it''.

But Ms Gallagher said the service was not appropriate because the Assembly should not appear to be promoting one faith over others.

''The Assembly is secular and Mrs Dunne involving the Christian Lobby to try and create a religious divide is precisely why such a ceremony will not gain the support of this government,'' she said.

Mrs Dunne declined to comment further on the matter, including the ACL's involvement.

But last week, the Speaker criticised the Chief Minister's stance.

''I think it sends an unfortunate message to the people of the ACT: that people of faith are not important to them,'' she said. ''If you're a Buddhist or Christian, or any faith, there's not a place for this in the public square.''

Mrs Dunne said the service was for Canberrans of all faiths and it would make the Assembly more accessible for the broader community.

''Are we saying that people of faith can't come together and pray on the outcomes of the Legislative Assembly for the ACT?

''Is that what the Chief Minister is saying?

''It's not just for the Assembly - it's for the community.

''We make decisions on behalf of the community and there are people in the community who would welcome the opportunity to pray for the people that make those decisions for them.''