Glasgow Council originally promoted the event
Protests are being mounted as Glasgow plays host to a military defence conference this week.
More than 1,100 delegates from around the world are attending the Undersea Defence Technology conference.
Campaigners have slammed Glasgow City Council and Glasgow Life for supporting the fair.
Scotland Against Militarism and Campaign Against Armed Trade (CAAT) Scotland are staging protests outside the conference taking place at the Scottish Event Campus.
Rev Dr Richard Frazer, convener of the Church and Society Council of the Church of Scotland, criticised Glasgow council for allowing the event to go ahead.
He said: "We are disappointed that Glasgow City Council has chosen to support an international festival of the arms trade.
"To facilitate such a gathering is deeply uncomfortable at a time when so many innocent people around the world are suffering from effects of war and the damage and destruction caused by weapons.
"Such a venture may bring income for some Scottish businesses, but we should be investing in a future that brings conflict and the need for weapons manufacture to an end.”
Susan Aitken, council leader, said the event had been decided before the SNP had taken over Glasgow Council.
She said: "The council is not responsible for the conference or contracts between conference organisers, the venue and accommodation providers.
"The contract was agreed before last May's local government elections.
“While we have a responsibility to support and promote the positive economic impact generated by the convention and events sector, we also understand that some people have expressed their opposition to this conference being held in the city.”
