OTTAWA -- A United Nations housing watchdog is taking the federal Liberals to task over what she sees as the government's about-face on a promise to put a human rights lens on its housing strategy.

In a scathing letter, Leilani Farha, the UN special rapporteur on the right to housing, says her support for the strategy is waning, based on indications that the Liberals "may not recognize the right to housing" in forthcoming legislation to enshrine the 10-year, $40-billion program into law.

A Liberal point man on the housing file told the Commons last week that the government didn't want to declare a right that creates a belief that people can "prosecute their way into housing" and that they need landlords, not lawyers.

Farha's letter called the government's position "discriminatory and patronizing."

In an interview, Farha said Ottawa can't create a rights-based housing strategy without formally and legally enshrining housing as a human right.

"At a time when human rights are so fragile around the world, with populist governments reacting against the multilateral human rights system, I would think the government of Canada -- which stands apart -- would do everything it could to embrace human rights," said Farha, who also heads the group Canada Without Poverty.

"Instead of embracing the recommendation and the right to housing, the government seems to be recoiling from it."

A spokesman for Social Development Minister Jean-Yves Duclos, the minister in charge of the strategy, said the Liberals plan to "recognize and progressively implement every Canadian's right to access adequate housing" in the coming legislation to ensure "Canadians have an adequate and affordable home."

The Liberals have promised to introduce legislation to make it difficult for any successive government to back out of the plan to help provinces and territories set long-term goals, instead of wondering how much they might receive year by year.

Farha's letter is aimed at putting pressure on the government as it spends the summer working on a bill that would also create a federal watchdog to track progress and identify systemic issues in the housing system.

Characterizing housing as a human right is meant to provide recourse, usually through tribunals, to anyone wrongfully denied a home for reasons such as ethnicity, religion, or gender identity, and to allow for watchdogs to conduct reviews to remove systemic barriers to housing.

"It's never been proposed as a charter amendment, or as a court to correct individual grievances," Adam Vaughan, Duclos' parliamentary secretary on housing, wrote on Twitter.

"It's about building a housing system that realizes peoples right (to) housing (through) progressive measures."

The government's efforts won't do much to deal with barriers that get in the way of expanding the supply of affordable homes, said Conservative critic Karen Vecchio, who cited red tape as one such barrier that vexes builders at the municipal level.

"Making it a right doesn't necessarily make it right," Vecchio said. "What we need to do is have avenues so that people can get into housing, whether it's rental housing or home ownership."

The NDP earlier this year unsuccessfully tried to have a right to housing added to Canada's Bill of Rights. The party's housing critic, Sheri Benson, said she wanted to see strong language on housing rights in the legislation the Liberals could table in the fall.

"How are we going to hold a government to account for a 10 year strategyΓÇªif you don't really have good legislation," Benson said.

"There's no way the public can hold the government to account if it (the legislation) doesn't have teeth, if it doesn't acknowledge that people have a right to housing."

Farha provided a vote of confidence for the national housing strategy when it was unveiled in November, but on the understanding that the accompanying legislation would recognize a right to housing. The government has pointed to her tacit support whenever questioned about on the topic.

In her letter, sent to Duclos and Prime Minister Justin Trudeau, Farha urged the government to stop using her words as a stamp of approval.