"We have committed ourselves in Germany to the market ramp-up of these fuels," he said in Hamburg, according to a transcript of his speech.

Earlier this month, the European Parliament adopted a deal to set binding targets for airlines in Europe to increase their use of SAFs, which have net-zero CO2 emissions or lower CO2 emissions than the fossil fuel kerosene.

Industry representatives, including Lufthansa CEO Carsten Spohr, have warned that reaching the targets will not be possible with today's production, with SAFs currently making up just a fraction of airlines' fuel.

(Reporting by Andreas Rinke, Writing by Rachel More, Editing by Friederike Heine)