German airline Lufthansa said Tuesday it has offered compensation of 25,000 euros ($27,900) to the families of the German passengers who were killed in the Germanwings crash in March, a sum dismissed as "completely inadequate" by the families' lawyers.

Lufthansa and its low-cost subsidiary Germanwings said that in addition, each of the victim's immediate surviving kin -- parents, children, adopted children, spouses and partners -- would each receive 10,000 euros.

But the families' lawyer Elmar Giemulla said in an emailed statement that the offer was "completely inadequate."

Prosecutors believe that the jet's 27-year-old co-pilot Andreas Lubitz deliberately crashed the Airbus A320 into a French mountain on March 24, killing all 150 people on board, including 72 Germans.

After the crash, Lufthansa offered aid of up to 50,000 euros per passenger to their relatives, independent of any eventual compensation payments.

In a joint statement Tuesday, Lufthansa and Germanwings said they would assume the "long-term responsibility for the outcome of the crash".

Hence, children and teenagers who had lost one parent or both parents would receive support for their education in the long term from a special fund of up to 7.8 million euros.

An additional fund was also being set up to provide individual support for aid projects of the relatives.

In addition, Lufthansa and Germanwings said that memorials would also be set up in four locations affected by the tragedy, with commemorative plaques to be installed at Barcelona airport and at the company headquarters of Germanwings in Cologne.

A "room of silence" would be set up in the vicinity of the location of the crash in Le Vernet.

Among the German victims were a group of school children from the town of Haltern who were returning from a school trip of Barcelona.

Trees had already been planted in Haltern in their memory, Lufthansa said.

"The relatives of the victims and their lawyers shall be informed on further compensation over the next few days," the statement said.

In April, Lufthansa said $300 million in provisions had been earmarked to cover the damages.

The sum includes financial compensation for the families of the people who died and the cost of the Airbus A320 jet itself, which has a current list price of $93.9 million.