The chemical firm is heavily involved in the project

Degussa was chosen to supply an anti-graffiti coating for concrete slabs which make up the memorial.

But the revelation of its past links to a company producing Zyklon-B - the poison gas used in the death camps - led to calls for it to be shunned.

The head of the memorial's trustees said it had been a difficult decision.

"It was a very intensive discussion and we made a difficult decision," Wolfgang Thierse, who is also speaker of the German parliament, told reporters in Berlin.

"We decided to carry on construction of the memorial under the current agreements and with all the firms who had contracts."

Degussa at one time held a major stake in Degesch, the supplier of Zyklon B gas pellets during the Nazi era.

Deep involvement

This issue sparked an emotional debate in Germany after leading members of the memorial board first moved to exclude Degussa from the project in September.

The laid slabs will give the impression of a vast graveyard

Some critics of the move, including the architect of the memorial, pointed out that Degussa actually had an exemplary record in being open about its past and contributing to compensation funds.

The issue became broader, with newspaper editorials and politicians asking whether German atonement for the Holocaust was actually being accepted.

The BBC's Berlin correspondent, Ray Furlong, notes that the irony is that Degussa's anti-graffiti coating was supposed to protect the memorial from defacement by neo-Nazis.

And there was also a practical element: a Degussa affiliate was involved in building the foundations, so excluding the company could have meant knocking down what has been built so far and starting again from scratch.