A Plaid Cymru AM has accused a party colleague of undermining its policy on the right to buy council houses.
Bethan Jenkins demanded Neil McEvoy delete a Facebook post objecting to Welsh Labour ministers' plans - backed by Plaid - to stop council house sales.
Mr McEvoy said right-to-buy was the "one realistic way" many working-class people had of owning their own home.
But Ms Jenkins, the party's housing spokeswoman, said social housing should not be sold off.
A bill to abolish the right-to-buy is currently making its way through the Welsh Assembly, although a number of councils have already been given permission to suspend the policy.
They include Cardiff, where Mr McEvoy is also a councillor.
On September 8 he posted a video to Facebook of a speech in the assembly earlier this year where he protested against the Welsh Government's policy.
In a comment alongside the video, he said: "Sell council houses to working-class people. Use the money to build new ones. Seems simple enough. Not after this room full of multiple home owners, led by Labour, banned the sale of Council houses.
"That was the one realistic way people on the estates had of owning their own home one day. Not anymore."
Ms Jenkins, in a public reply on Facebook, told Mr McEvoy: "I strongly suggest you take this post down.
"Following INTERNAL email conversations I told you in no uncertain terms that Plaid policy is to support ending the right to buy."
She said the party's policy had been stated "time and again".
"I think you own your own home so please do not take the moral high ground here," she said.
"You are actively undermining that view, the party policy of Plaid Cymru, and the work myself and [Plaid AM] Sian Gwenllian have done on the committee looking at this legislation. Social housing is necessary to keep as that - social.
"We cannot sell off more homes so that they are off the market and unable to be accessed."
Ms Jenkins's post has since been deleted.
Mr McEvoy has been critical of his party's "compact" with Welsh Labour, which remains in power in return for consultation and concessions on a range of issues.
In August, he called on Plaid Cymru to "embrace full-on opposition" instead of "meekly seeking to 'influence' Labour".