Beattie apologies for saying DUP were "whining like a girl"
He told MLAs he "got it wrong" with the remark.
Ulster Unionist leader Doug Beattie has apologised after he claimed in the Northern Ireland Assembly that DUP MLAs were screaming and whining "like a girl".
Mr Beattie, who this year was involved in a controversy over historical tweets, told MLAs he "got it wrong" with the remark.
The Assembly met on Wednesday during a recalled session in a doomed attempt to elect a new speaker to revive the powersharing institutions.
During his speech, the UUP leader told DUP members: "I know that you think you can scream and whine like a girl from the sidelines. That's up to you."
Several MLAs voiced objection to the remark from their seats in the chamber, while DUP MLA Philip Brett raised a point of order with Acting Speaker Alan Chambers.
Mr Brett appeared to make reference to the previous controversy when Mr Beattie apologised after being accused of misogyny over the contents of a series of historical tweets.
"Mr Speaker, the house will be aware of Mr Beattie's history when it comes to misogyny but I'm just wondering is it in order, Mr Acting Speaker, to use such language in relation to women in this chamber?" he asked.
In response, Mr Chambers said: "The member is perfectly entitled to say whatever he wishes."
Mr Beattie resumed his speech with an apology.
"I'm a big enough man to say when I get something wrong. I got it wrong and I will apologise because I got it wrong, because I used a terminology," he said.
Earlier this year, Mr Beattie said he came "very close" to quitting as party leader when a series of derogatory tweets he posted prior to entering political life came to light.
The Upper Bann MLA faced accusations of misogyny and racism over comments he posted when he was still serving as a captain in the Army.
The furore erupted when Mr Beattie tweeted a joke which referred to the wife of political rival Edwin Poots and a brothel.
It escalated after focus turned to Mr Beattie's historical conduct on Twitter and a series of contentious remarks about women, Muslims, Travellers and people with mental health issues were unearthed.
At the time, Mr Beattie implored people not to define him by his past after receiving party backing to continue as leader.