Russia's Gazprom has cancelled a tender for construction of around half of its Power of Siberia gas pipeline to China worth almost 156 billion roubles ($2.2 billion), it said in a regulatory filing on Dec. 29.

A spokeswoman for Gazprom declined to provide immediate comment.

Russia's FAS federal anti-monopoly body had questioned the tender's compliance with regulations.

In a separate tender last week, Gazprom awarded Stroygazmontazh, owned by Arkady Rotenberg, an ally of Russian President Vladimir Putin, contracts worth almost $3 billion for work on the pipeline.

The pipeline is designed to deliver 38 billion cubic metres of gas per year to China over 30 years, with first deliveries scheduled for 2019.

($1 = 72.3825 roubles)