Speaking on Thursday before the BND secret service parliamentary committee, Steinmeier said it was "correct" to have blocked Kurnaz' return to Germany in light of the country's security concerns after the Sept. 11 attacks in 2001.

There were "good reasons" why Kurnaz had been categorized as a possible radical-Islamist "sleeper" and a security risk, Steinmeier told the committee, which is investigating cooperation between the former Social Democratic-Green party coalition under Gerhard Schröder with the Unites States' "war on terror."

Kurnaz was arrested in Pakistan just weeks after Sept. 11 and handed over to US authorities. He eventually landed in the US detention center in Guantanamo Bay, Cuba, where he says he was tortured until his release without charges in August 2006.

Vote against Kurnaz' return

In October 2002, Steinmeier -- who was then Schröder's chief of staff -- led a committee of German secret service officials which voted against allowing Kurnaz to return to Germany. Steinmeier has denied the United States offered to release Kurnaz in 2002, as has been alleged by German media.

"The US never considered releasing him," Steinmeier said.

He also stressed that the government had "tried many times to intervene" in the case, but the plan was to return Kurnaz to Turkey, where he had citizenship, rather than to Germany, where Kurnaz had been born but for which he only had a residence permit.

"In October 2002, Germany was considered to be a direct target for attacks," the foreign minister said.

"Attack warnings came on a weekly basis. We reckoned with an estimated 3,000 sleepers," he said. "Top secret service officers described Mr. Kurnaz in October 2002 as a security risk, and I had no reason to doubt these assessments."

Steinmeier said that even today, he believed the decision was "justified."

Interior ministry responsible

Earlier on Thursday, Germany's former interior minister, Otto Schily, claimed political responsibility for the handling of the Kurnaz case, taking some of the pressure off Steinmeier.

Schily, who was interior minister under the Schröder, told the committee he was responsible for all government "actions and omissions."

Schily said there was no doubt that the Interior Ministry -- and not the Chancellery or the Foreign Ministry -- had "the core responsibility for the valuation of security cases."

"Steinmeier had to rely on the proper, careful analysis of the facts carried out by the Interior Ministry and the intelligence services," Schily said, adding that the government's conduct had been "perfectly correct."

Kurnaz was freed after Chancellor Angela Merkel came to power due to a lack of proof that he belonged to a terrorist group. He lives in the northern German city of Bremen.