A former DUP constituency association chairman has claimed vehemently eurosceptic members of his party are holding too much sway over its Brexit policy.
David Cather, who was previously chairman of the DUP's South Belfast association, said the party was no longer reflective of the "broad church" he once believed it represented.
But Sir Jeffrey Donaldson has defended the DUP's stance, saying it has been avowedly eurosceptic since Britain first joined the EEC.
"The direction of this party is a matter for the executive and party officers – they set the direction," he told The Irish News.
"Since the UK joined the EEC, we have fought elections on a manifesto that was opposed to European membership, so it really should not come as a surprise to anybody who is a DUP member."
Mr Cather, who remains a party member and advocates remaining in the customs union, said it had been a "frustrating couple of years" to be in the DUP.
"When we announced our position on the referendum, the leader's statement very much sounded like we were going to be a broad church and there would be different opinions within the party," he told the BBC.
"That never really materialised and suddenly we ended up taking out (pro-Brexit) adverts in London."
During the EU referendum campaign, the DUP took out a wraparound ad in the Metro newspaper urging voters to "take back control".
He said the party's Brexiteers were wielding too much power.
"I think that the people who really want to leave have been given too much control over the direction," he said.
Mr Cather added that he was not in favour of overturning the referendum result and was not in favour of a second referendum "at the moment".
"But, I would reserve the right to call for it if parliament can't sort it out."
