German intelligence says that an official with the Hezbollah terror group admitted that Syrian President Bashar Al-Assad ordered a poison gas attack last month.

According to a report in the Reuters news agency on Wednesday, Hezbollah considered the move a mistake which showed Assad was losing his grip.

Participants at a confidential meeting of German lawmakers on Monday said the head of the BND foreign intelligence agency told them it had intercepted a phone call believed to be between a high-ranking member of Hezbollah and the Iranian Embassy in Damascus.

“The BND referred to a phone call they had heard between a Hezbollah official and the Iranian embassy in which he spoke about Assad having ordered the attack,” one of the participants told Reuters on Wednesday.

In the phone call, the Hezbollah official says Assad’s order for the attack was a mistake and that he was losing his nerve, the participants reported the BND briefing as saying.

A BND spokesman declined to comment on Monday’s briefing, saying German intelligence speaks only to the government and to parliamentary committees on highly sensitive matters.

A Hezbollah spokesman was not available for comment.

The German weekly Der Spiegel reported this week that the BND has enough evidence in its possession to conclude that Assad ordered the suspected chemical attack in Syria on August 21.

According to Der Spiegel, BND President Gerhard Schindler voiced his support for U.S. allegations that Assad‘s government ordered the attack on the eastern Damascus suburb of Ghouta.

The intelligence agency’s chief said that following a thorough analysis his ministry assumes that the regime is the perpetrator of the chemical attack which killed hundreds of people.

The U.S. government said about 1,400 people, hundreds of them children, died in what it says was a sarin gas attack by the Syrian government.

On Sunday, U.S. Secretary of State John Kerry said that the administration had new evidence that sarin gas was used in the chemical attack.

“We know that the regime ordered this attack,” he said. “We know they prepared for it. We know where the rockets came from. We know where they landed. We know the damage that was done afterwards.”

French intelligence has also shown the chemical attack came from government forces.

A dossier shared with the French parliament this week reportedly includes satellite images showing a large offensive on the Damascus neighborhood of Ghouta coming from government controlled areas to the east and west of the area held by rebel forces.

One participant at the Berlin meeting told Reuters German lawmakers of all parties were skeptical about a military intervention in Syria and had quizzed the BND over faulty intelligence on weapons of mass destruction in Iraq used to justify the U.S.-led invasion of 2003. No such weapons were found.

Some German lawmakers also expressed concern that German intelligence on Syria could be used by the United States to justify military intervention without a UN mandate.

Berlin has ruled out participation in a military intervention in Syria, which would be deeply unpopular at home.