BERLIN: Thousands of pilots have gone back to work at German airline Lufthansa after a strike was suspended but the carrier is warning that it won't return to its normal schedule until Friday.

Lufthansa said Tuesday that the "consequences of the strike will lead to continued flight irregularities in the following days." At Berlin's Tegel airport, several of its flights were canceled and passengers were seeking seats on rival Air Berlin PLC.

Some 4,000 Lufthansa pilots went on strike Monday over their concerns that cheaper crews from Lufthansa's smaller airlines in other countries could eventually replace them.

The two sides agreed to suspend the walkout until March 9 and resume talks.

Pilots for Lufthansa Cargo and the low-budget subsidiary, Germanwings, had also taken part.