Following German parliamentary approval for military involvement in the fight against Islamic State in Syria, the German Army has demanded an increase in troops.
"We currently need at least 5,000 to 10,000 more soldiers," Bundeswehr union head Andre Wuestner told Saturday's edition of the Passauer Neue Presse.
The increase was also necessary "because from January a new labour law takes effect and round-the-clock service for basic operations will quite rightly no longer be permissible," he said.
Wuestner added that the reduction in the Bundeswehr's numbers had gone too far in the past. "In the reform of 2011 nobody could foresee the crisis Ukraine or the fight against Islamic State," he said.
Politicians did not know then that there would be 20,000 troops needed in 2016, for military activities and similar duties such as dealing with the refugee crisis.
"Now the Afghan mission will be extended and we will soon increase our involvement in northern Iraq and Mali," he said, adding that the upper limit for troop numbers must be increased and equipment improved.
On Friday, the Bundestag, or lower house of parliament, approved a year-long German military involvement in Syria, with up to 1,200 troops expected to take part in the fight against the Islamic State terrorist organization.
The head of Chancellor Angela Merkel's office stressed on Saturday that Germany would not cooperate with Syrian President Bashar al-Assad in the fight against Islamic State.
"For Germany and the European Union it is clear that we will neither cooperate with Assad nor the Syrian Army," Peter Altmaier told Der Spiegel news magazine.
"The Syrian Army and Assad with his barrel bombs have contributed to the fact that hundreds of thousands of people have fled to the north of Syria and from there on into Turkey and Europe," he said.
Germany is facing a huge explosion in the number of refugees this year, many fleeing the war in Syria, and could see around 1 million people applying for asylum, up from just over 200,000 in 2014.
Meanwhile, the Central Council of Muslims in Germany criticized the decision to become involved in Syria, saying the best way to fight terrorism was to stop delivering weapons to the terrorists.
Council chairman Aiman Mazyek told Saturday's edition of the Neue Osnabruecker Zeitung that the regional powers should also be forced to sit round the negotiating table.
A powerful concept of reconciliation and peace was needed to counter the perspective of misery and death and illustrate life instead, he said. "This is how to dry up terror and dictatorship around the world."
Mazyek said Islamic State and al-Qaeda had arisen as a "result of a war policy that had gone completely awry."
"We sowed war, and refugees and terror appeared," he said.