A UN report on housing has been called a "wake-up call" for the Government by the leader of Sinn Féin.
The report by UN special rapporteur Leilani Farha criticises the Government for allowing multinational "vulture funds" to buy up properties and rent them out at high rates.
The report states that "landlords have become faceless corporations wreaking havoc with tenants".
In the Dáil, Mary Lou McDonald said the report was a damning condemnation of the Government's record on housing.
She said the report condemned the Government for "facilitating the financialisation of housing by providing preferential tax rates to corporate landlords and by standing over weak tenant protections".
Ms McDonald said the report accused the Government of allowing corporate interests to trump the needs of ordinary families in the housing market.
She asked the Taoiseach to accept Sinn Féin proposals to introduce a three-year rent freeze, and to support legislation by her colleague Eoin Ó Broin, which would prevent buy-to-let landlords from seeking vacant possessions.
Responding during Leaders' Questions, Leo Varadkar said he had not had a chance to read the latest UN report in full.
However, he said he accepted that the figure of 10,000 homeless people in Ireland is too high.
Mr Varadkar said the solution to the problem is supply, and while the Government is lifting thousands of people out of homelessness every year, the same number are becoming homeless and this has made it difficult to get the numbers down.
He dismissed a claim by Ms McDonald that the Government was wedded to the ideological view that the market would sort out the problem.
He said he did not see the problem in ideological terms and that all sorts of housing was needed, including social and private housing.
Mr Varadkar said if it was the case that this Government only believed the market could produce solutions by the private market, it would not have built social houses, or introduced rent controls, or derelict site levies.
He said the Government would not support Sinn Féin legislation preventing landlords from selling their buy-to-let properties because the bill would be unworkable and cannot be applied retrospectively.
The Taoiseach also said that it is likely to be unconstitutional because it may infringe on property rights.