European natural gas prices jumped on Monday after flows reversed on a key pipeline that moves Russian supplies to the continent. 

Monday’s price action was the latest to demonstrate how mixed signals from Russia have the European market seesawing. The Dutch Title Transfer Facility and National Balancing Point benchmarks dropped sharply last week, falling from over $30/MMBtu to near $20 after it seemed more Russian supplies were headed for the continent, which is short natural gas heading into the winter. 

Prices bounced back Monday and settled above $22 after data from grid operator Gascade showed that flows reversed over the weekend on the Yamal-Europe pipeline, with volumes moving eastward toward Poland instead of Germany. Similar flows were seen Monday. 

The reversal...