NATO is planning to build a pipeline system from Germany to Poland and the Czech Republic to ensure a rapid supply of jet fuel for fighter aircraft in the event of a war with Russia, weekly German magazine Der Spiegel reported.

The existing Cold War-era pipeline system of the military alliance currently ends in western Germany.

Der Spiegel cited an internal memo from the Bundeswehr - Germany's armed forces - as stating that there are "significant problems in the sustainable fuel supply for forces that would need to be deployed to the eastern border in case of emergency".

Neither NATO nor the German defence ministry immediately replied to requests for comment.

According to a separate briefing document for the senior leadership of the German defence ministry, internal discussions among NATO allies have concluded that pipeline systems are "the backbone of NATO’s fuel supply", Der Spiegel wrote.

The project is expected to cost 21 billion euros ($22 billion), with the pipeline expected to be largely completed by 2035, according to the Der Spiegel report.