The European Parliament joined the controversy over 2022 World Cup host nation Qatar's treatment of migrant workers on Thursday when it passed a resolution expressing concern at their plight.
However, it stopped short of calling for the abolition of the Kafala, or sponsorship, system under which employees cannot change jobs or leave the country without the permission of their sponsors.
"The European Parliament is concerned about the situation of the migrant workers in Qatar," said the resolution. "MEPs call on the Qatari authorities to stop detaining individuals for 'running away' from their employers.
"MEPs note that at least 500,000 more migrant workers are expected in Qatar to accelerate work in preparation for the 2022 football World Cup there," it added following a session in Strasbourg.
"(They) urge FIFA to send a clear and strong message to Qatar to prevent the preparations for the 2022 football World Cup being overshadowed by allegations of forced labour.
"MEPs appeal to the European corporations involved in building stadiums or other infrastructure projects in Qatar to provide working conditions that are in line with international human rights standards."
Amnesty International, Britain's Guardian newspaper and the International Trade Union Confederation have delivered scathing reports on the treatment of migrant workers in Qatar in the last few months.
The reports say the construction industry is rife with abuse of migrant workers who often work long hours in searing heat, live in squalid accommodation and are sometimes denied their wages.
The Greens had wanted the resolution to mention the Kafala system.
"The resolution adopted today sends an important signal both to the Qatari government and international football authorities on the need to take urgent action to address the situation regarding forced and slave labour in Qatar," said Green MEP Barbara Lochbihler in a statement.
"While we regret that centre-right MEPs succeeded in removing a core demand, calling for the abolishment of the Kafala system, the resolution nonetheless highlights the fundamental flaws of this system, which pushes thousands of migrant workers into a situation of forced labour.
"We would urge the Qatari government to repeal the Kafala system as a matter of urgency and for FIFA to prioritise this in its relations with Qatar in the context of the world cup."
Before the session, Lochbihler had criticised FIFA's response to the reports.
"The response of FIFA to date has been hesitant," she said. "FIFA must have been aware of the existing problems in Qatar before awarding the country the World Cup. They should have conditioned their decision on the implementation of concrete human rights reforms, but decided to simply push ahead.
"It is not too late for FIFA and UEFA to at last shoulder their responsibility. Together with the active support of its European members, FIFA must send a clear message to Qatar to take immediate steps to address the human-rights situation of migrants."
FIFA said it "welcomed" the European parliament's resolution but could not change the situation alone.
"In order to achieve a sustainable improvement of working conditions in Qatar and the wider region, a joint effort by FIFA, the business sector, the international community and the Qatari authorities is required," said FIFA.
"FIFA remains open to cooperate with all relevant bodies and authorities to tackle this issue and to ensure that the protection of migrant workers continues to be addressed with urgency."
Earlier this week, an unnamed source at Qatar's foreign ministry told the state news agency QNA that the Gulf state "attaches great importance to the promotion and protection of human rights".
The source said the government had on October 3 appointed the international law firm DLA Piper to conduct an independent and comprehensive review of the issue of migrant worker abuse.
(Reporting By Brian Homewood; Editing by Alison Wildey)