"Economic and political leaders must contribute to improving the unacceptable situation in Qatar," Blatter said after talks in Zurich with Michael Sommer, head of the International Trade Union Confederation.
Sommer, who also leads Germany's union confederation, has demanded that FIFA give Qatar an ultimatum to halt what critics say are forced-labour style conditions or be stripped of the World Cup.
Blatter's sit-down with Sommer at FIFA's headquarters in Switzerland, was brokered by German Football Association chief Wolfgang Niersbach.
"The awarding of the World Cup and the considerable public exposure give us the opportunity to point out irregularities and to exact lasting change, Niersbach said Wednesday.
"If we succeed, then a lot will have been achieved."
FIFA's decision to name Qatar the host of the 2022 edition of global football's top tournament has been dogged by controversy from the outset.
While debate rages in the sports world over whether to shift the tournament from its traditional June and July dates to escape the scorching Gulf heat, the focus of human rights and labour activists over recent months has been squarely on the treatment of workers.
On Monday, Amnesty International urged the energy-rich emirate to end the abuse of migrant construction workers, largely from South Asia.
In response, the organizing committee in Doha, which rejects claims of slavery-style conditions on construction sites in one of the world's wealthiest nation per capita, pledged to impose respect for workers' rights.
Blatter visited Qatar on November 9th and received what FIFA said was a "firm commitment" on the issue from its emir, Sheikh Tamim bin Hamad al-Thani.
"I am convinced that Qatar is taking the situation very seriously," Blatter said on Wednesday.
Qatar has said its labour laws are being amended, and that government inspectors are to receive more powers to enforce the legislation.
Sommer challenged Qatar to respect international labour standards, in order to "eliminate discrimination and forced labour as well as allow freedom of association for its 1.3 million migrant workers".
Theo Zwanziger, the former head of German football who is the FIFA executive committee member overseeing the labour rights issue, said clear steps were expected within months.
"The aim is to be in a position to report on concrete measures for Qatar at the executive committee meeting in March 2014," Zwangziger said.
It was also up to the business world to do its part, he said.
"Large companies must be reminded of their duties in this area.
"The international community must also accept its responsibility."