SDLP leader Colum Eastwood has called for the DUP's Sir Jeffrey Donaldson to make clear his objections to methods of teaching of relationship and sex education (RSE).
It follows an invitation issued to a parliamentary briefing last night by the Lords and Commons Family and Child Protection Group (LCFCPG), of which the DUP MP is chair.
The group was prominent in the campaign that backed Section 28, which effectively banned teaching about gay relationships in the 1980s.
Mr Donaldson claims in the invitation that in some cases RSE, which becomes mandatory for schools in England from September 2020, was being "taken over by ideologues and special interest groups who wish to promote their own agendas which in a number of cases are leading to serious child protection and safeguarding issues".
"We wish to alert parliamentarians to the dangers involved and the potential increase in emotional, psychological and physical harms that are already arising due to the way RSE is being handled in some schools."
He said the briefing was due to be addressed by an "expert panel", which was scheduled to include a pastor who opposes gay marriage and believes RSE is “sexualising” children.
Rev Lynda Rose, who was ordained by the Church of England as a priest in 1994 and also leads the anti-abortion pressure group Voice for Justice, is joint convenor of the LCFCPG.
She describes herself as resisting “a growing tide of darkness” and “a neo-pagan battle for supremacy” linked to same-sex marriage.
Mr Eastwood called on the DUP to clarify the motivation behind last night's Westminster event.
"Many will have concerns about the DUP interest in RSE given their historical opposition to LGBT+ equality and the decriminalisation of homosexuality – as the chairman of this group, Jeffrey Donaldson should make his objections to methods of RSE teaching public," he said.
The Foyle MP said inclusive RSE was an "important part of the curriculum".
"It should not be subject to the prejudices of anyone and should give representation to everyone," he said.
"I sincerely hope that this event is not designed to cause further damage to a community that has been the subject of political attack for far too long."
A DUP spokesman said the event had not been organised by the party.
"It is a briefing to the Lords and Commons Family and Child Protection Group and Sir Jeffrey Donaldson’s role is to chair the event," he said.
"Those providing the briefing are obviously responsible for the content and they will provide any commentary at that time."
