The Nord Stream 1 gas pipeline has been the focus of a spat between Russia and EU members in recent weeks, as Brussels seeks to secure sufficient reserves to get member states through the coming European winter.

Gazprom, Russia’s state-controlled gas giant, has kept European leaders on their toes as it repeatedly announced disruption in gas flows due to what it claimed were technical issues due to maintenance work.

On Tuesday, as the bloc’s energy ministers met in Brussels to approve an emergency plan, EU energy policy chief Kadri Simson slammed Gazprom’s announcement that it would reduce flows to 20 percent of the pipeline’s capacity as “politically motivated”.

Here is what you need to know:

Why does Nord Stream 1 matter?

• Nord Stream 1, which is majority-owned by Gazprom, is the single biggest pipeline bringing crucial supplies of Russian natural gas to Europe via Germany.
• The EU is heavily reliant on Russian gas. Last year, Russia supplied some 40 percent of the EU’s natural gas.
• That has dropped significantly this year, straining energy-intensive industries and sending commodity prices through the roof.
• Maintenance work largely went unnoticed in the past, but the pipeline has now become a bargaining chip as Russia and the West exchange economic blows in response to Russia’s full-scale invasion of Ukraine launched in February.

What has happened so far?

• Russia cut flows through Nord Stream 1 to 40 percent of capacity in June, citing the delayed return of a turbine that was being serviced by Siemens Energy in Canada. Germany rejected the explanation, saying there was “no technical justification” for the reduction.
• Moscow then shut the pipeline altogether for 10 days of annual maintenance this month, restarting it on July 21 still at 40 percent of normal levels.
• On Monday, Gazprom announced it was halting the operation of one of the last two operating turbines of the Nord Stream 1 pipeline due to the “technical condition of the engine”.
• It added that deliveries to Europe via the pipeline were to be reduced to about 20 percent of its capacity from Wednesday.
• EU energy policy chief Kadri Simson on Tuesday said, “We know that there is no technical reason to do so,” adding that the EU had to counter Moscow’s moves by pre-emptively reducing gas consumption.