Furniture manufacturer and retailer Ikea has denied claims to be made by a Swedish television documentary that the company used East German political prisoners as forced laborers at its factories in the former Communist state during the 1970s and 1980s.

According to The Local, an English-language Swedish newspaper, Sveriges Television's (SVT) Uppdrag Granskning program reportedly uncovered corroborating evidence in the archives of Stasi, the former East German secret police agency. The documentary is scheduled to air on Wednesday in Sweden.

A German television program made similar claims last summer that asserted Ikea company officials fully cooperated with the East German government in the then-hiring of prison workers.

After the German documentary, Ikea examined the issue to get a more complete picture of what happened. We have so far found no evidence to suggest that political prisoners were used in [furniture] production, Ikea said in a statement.

Ikea also stated that it conducted regular inspections of its factories in East Germany at the time.

We were clear in our demands then as we are now, the firm stated.

Ikea's social and environmental manager Jeanette Skjelmose told the Swedish news agency TT over the weekend: We have requested documents from the old Stasi archives and are interviewing people at Ikea who were around back then. So far there are no indications that we would have asked that prisoners be used in manufacturing or known about it.”

She added: What we're looking into now is whether it could have happened anyway, without our knowledge.”

The Local indicated that Ikea had 65 manufacturing facilities in East Germany during the 1970s. The German documentary from last year revealed that one of the factories, which made sofas, was located next to a prison in the city of Waldheim. An ex-prison chief told Germany’s WDR network that it was routine to use prison labor in the production of furniture.

Ikea has previously faced other controversies. Last year, it was revealed that Ikea’s billionaire founder Ingvar Kamprad was a member of the Swedish Nazi party during his youth.

Ikea is the world’s biggest furniture retailer, with annual sales of 25 billion euros ($33 billion) and about 131,000 employees.