Football's governing body has given Qatar two weeks to explain how it is improving welfare and living conditions for workers building World Cup 2022 projects.
FIFA says it expects to be sent "information on the specific steps" that have been taken since its president Sepp Blatter visited Qatar after rights groups criticized conditions for migrant workers from countries like Nepal, Pakistan and Bangladesh.
Jerome Valcke, FIFA's secretary general, wrote to Qatari organizers on Thursday asking for a "detailed report on the improvement of working conditions" by February 12.
FIFA executive committee member Theo Zwanziger is working with the International Trade Union Confederation to resolve concerns about Qatar.
"What we need are clear rules and steps that will build trust and ensure that the situation, which is unacceptable at the moment, improves in a sustainable manner," he said.
Qatari organisers said last year that companies building projects for the World Cup are to be forced to guarantee welfare standards for workers, in response to a critical report alleging abuses.
The organising committee, Qatar 2022, said it had informed the human rights group Amnesty International that it would create a worker welfare committee, and would publish a workers' welfare standards guide.
In November Amnesty catalogued a number of abuses against migrant workers building the infrastructure required for football's showpiece tournament.
Qatar's World Cup supreme committee said in reply: "Compliance with the law and Q22's standards will be a contractual obligation for companies working on Q22 projects and will be transparently and robustly monitored through a three-tier compliance and auditing structure."
It said that the standards would be aligned with Qatari law and best international practices.