The chairman of Labour's ruling national executive committee (NEC) has apologised after making an anti-Catholic comment on stage at party conference.

Andy Kerr was taking questions from delegates in Liverpool on Sunday and invited a woman in the audience to speak.

He then appeared to mock her for blessing herself, asking the delegate: "Did you cross yourself, there? In that case, I might not."

Kerr, from Glasgow, later described the remark as "ill-judged".

It met with a storm of criticism on social media and from politicians including Nicola Sturgeon, Holyrood's presiding officer Tricia Marwick and Scottish Labour leader Richard Leonard.

The SNP has called for Kerr to be stripped of his top position on UK Labour's NEC.

Leonard told the BBC: "There is absolutely no room inside the Labour party for that kind of remark, whether it's meant as a form of humour or not.

"It's completely unacceptable... there should be no space for it inside the Labour party and I condemn it."

The Scottish Labour leader will speak at conference later, committing the UK party to opposing a second independence referendum in its next manifesto and calling for a "federal Britain".

Following Kerr's comment, Marwick called on Leonard to take action against sectarianism within his party.

She tweeted to him: "The sectarian remarks today against Catholics by your chair Andy Kerr in an open session of your conference were disgraceful.

"What are you going to do about that?"

The First Minister also took to social media, describing Kerr's remark as "appalling".

She said: "Andy Kerr's comment was appalling. The Catholic community is an integral and valued part of Scottish life.

"Everyone who stands for a Scotland where bigotry and sectarianism have no place, and where we positively embrace diversity, must unite to condemn - regardless of party."

The SNP further called for Kerr to vacate his position as NEC chairman, describing it as "untenable".

A party spokeswoman said: "Sectarianism is an extremely serious issue and it is important that Labour treats it as such.

"It is untenable for Andy Kerr to continue as chair of Labour's NEC - he should go as a matter of urgency.

"Labour are developing a bad habit of trying to brush this kind of behaviour under the rug."

Kerr, who is also a deputy general secretary of the Communication Workers Union, said: "I apologise unreservedly.

"I was trying to be light-hearted but what I said was ill-judged and wrong."