BERLIN — Germany's transport ministry says it has asked local authorities not to enforce bans on Sunday driving for tanker trucks as suppliers thwarted by low river levels try to transport fuel by road.

A hot, dry summer and little significant rainfall since has left German rivers and lakes at record-low levels, and the Rhine — a major freight transport artery — has been particularly badly affected. Because of the low water, barges aren't able to transport full loads, raising the possibility of fuel shortages in western and southwestern areas.

Road transport is an alternative, but heavy trucks generally aren't allowed to drive in Germany on Sundays and public holidays. Transport ministry spokesman Ingo Strater said Monday the ministry has written to state authorities asking them to waive enforcement of the ban.