TORONTO -- Ontario's Progressive Conservative leader says he didn't know that a letter was being distributed with his name on it saying he would scrap the Liberal government's sex-ed curriculum.

The letter purporting to be from Patrick Brown was sent out last week in the east Toronto riding of Scarborough-Rouge River days before voters head to the polls Thursday in a byelection.

"Upon being elected, a PC Government would scrap the controversial changes to sex-ed introduced by Premier (Kathleen) Wynne and develop a new curriculum after thoughtful and full consultation with parents," the letter said.

But Brown now says that is not correct and he was unaware of the letter before it was distributed.

"I saw the letter after it went out," Brown told The Canadian Press.

"To be perfectly honest, as soon as I saw that I sent an assistant to grab all the literature and take it away and put it in her trunk because I didn't want it going out. It didn't reflect my views."

Brown wouldn't say who wrote the letter -- bearing his electronic signature and authorized by the CFO of the party -- but suggested it came from the Scarborough-Rouge River campaign.

"I'm not going to throw anyone under the bus," he said. "I'm leader of the party. I am responsible. I own it and I apologize."

The Liberals called on Brown to distribute new letters in the riding, translated into different languages, to clarify his position on sex ed because the majority of voters in the riding do not speak English as their first language.

"I hope that Patrick Brown works to correct the record to all voters in this community," said a statement from Liberal Michael Chan.

"Otherwise one has to wonder if the flip flopping is incompetence or political cynicism at its worst."

Brown said the "first thing" he did when he saw media reports about the letter on Friday was to compose a series of tweets to clarify his position -- though none directly refuted the idea that he would scrap the Liberal curriculum.

He then wrote an op-ed Monday and did a round of interviews Tuesday to disavow the letter even though doing so won't help the party's chances in the byelection, he said.

"There is significant opposition to the sex education curriculum in Scarborough-Rouge River," Brown said. "I know that for many in Scarborough not scrapping it will be an unpopular position."

The curriculum was updated last year, for the first time since 1998, but some parents complained that the government didn't consult them enough and others were angered by mentions of same-sex relationships, gender identities and masturbation.

If there is a Progressive Conservative government after the 2018 provincial election, Brown said he would consult parents during the next regular curriculum updated.

"But I'm going to be very clear: consulting doesn't mean no sex education," he said. "Consulting doesn't mean I'm taking out elements of the curriculum on combating homophobia or LGBT sensitivity...I think gender identity is part of the curriculum."