FIFA President Sepp Blatter backed calls from the European Union urging Qatar to stop companies from abusing migrant workers involved in construction for the 2022 World Cup.
"We deplore what happened there," Blatter said in Rome following an audience with Pope Francis on Friday.
The EU Parliament on Thursday said it wants a full investigation.
Qatari organizers pledged this week that companies building World Cup projects will be forced to guarantee welfare standards for workers.
The rights group Amnesty International has cataloged how some workers in the tiny Gulf nation face dangerous working conditions, poor living standards and nonpayment of wages.
"The big companies working there, they are all European," Blatter said. "The constructor is also responsible for his workers."
The International Trade Union Confederation set off the growing furor two months ago. It said that unless labor practices change at least 4,000 workers would die because of inhumane conditions.
Blatter implied the construction companies' interests played a role in the controversial vote to award the tournament to Qatar.
"It was political pressure from European countries to bring this World Cup to Qatar because there was so many economic interests," he said. "Two of these countries that made pressure on the voting men in FIFA were France and Germany. This is established. This is not new information.
"It's easy to say all the responsibility lies on FIFA. No, we are part of this responsibility. We are now monitoring the situation and we will come back to it."
Blatter reiterated his desire to hold the 2022 tournament at the end of the year, having rejected the traditional June-July World Cup period because of Qatar's searing desert heat.
"We are now consulting the stakeholders — teams, players, leagues, federations — about the international calendar, also media and marketing, to look if it's possible to play at the end of the year, in November-December," Blatter said. "I think it's advisable to play at the end of the year."
As for next year's World Cup in Brazil, Blatter said it's possible midday kickoff times at tropical venues could be moved to later in the day to avoid intense heat and humidity. Blatter said he will raise this issue at next month's FIFA executive committee meeting in Salvador, Brazil.
"(The start times) have been established but not sanctioned," he said. "It's a very important matter."
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