Housing and Communities Board chair David Ashford MHK says he doesn't know how many affordable homes planned by the government will be public sector housing.
He faced a question for written reply about the plan, announced in December, to provide 1,000 affordable homes over the next decade.
Mr Ashford said he doesn't know how many would be either general or sheltered public sector.
But he said he hoped to update Tynwald on the plans in April when the initiative begins.