New field will enable eventual exports to China via 'western route' through Altai Mountains.
Construction launched on 3,968 kilometre 'Power of Siberia' gas pipeline.
Altai route for gas to China could take priority, reported Reuters.
Gazprom subsidiary Tomskgazprom has announced the terminal to produce propane and butane mixtures.
Beijing reviewing its energy needs with slowing economy, says report.
Dignitaries gather on Chinese side of the pipeline to witness the formal welding of the first joint in $55billion line.
After months of speculation, parliament and President rubber-stamp deal that will see gas sent to China.
Agreement means Power of Siberia pipe could be delayed, it is claimed.
Gazprom says operations are 'in full swing' with work due to start soon on iconic pipeline to provide gas on eastern route.
Accident involving drilling works sparks massive blaze but thankfully no injuries.