On February 24, Russia invades Ukraine. Gas and oil prices soar on fears of possible cuts in supplies.
On March 2, the European Union cuts seven Russian banks off from the SWIFT banking transfer system.
But it spares two major lenders with strong ties to the energy sector, reflecting the dependence of several EU states on Russian gas.
On April 27, Russian giant Gazprom cuts off gas supplies to Bulgaria and Poland, in a move European Commission chief Ursula von der Leyen describes as "blackmail".
She says the two EU and NATO members are now receiving gas from their EU neighbours.
On May 21, Russia cuts gas to neighbouring Finland, which has refused to pay in rubles and angered Moscow by asking to join NATO.
The Netherlands and Denmark are also cut off after refusing to pay in rubles.
On May 30, EU leaders agree to stop most Russian oil imports by the end of the year but put off a ban on Russian gas.
On March 8, President Joe Biden bans US imports of Russian gas and oil. The EU says it will cut its imports of Russian gas by two-thirds this year and Britain says it will phase out its Russian energy imports by the end of 2022.
On July 11, Gazprom begins 10 days of routine maintenance on its Nord Stream 1 pipeline, resulting in gas cuts in Europe.
A week later, the EU and Azerbaijan sign an agreement to double gas imports from the energy-rich Caspian nation to Europe.
The 27-nation bloc has also turned to oil-rich countries such as Qatar, Norway and Algeria to make up for its energy shortfall.
On July 20, the European Commission urges EU states to reduce demand for natural gas by 15 percent over the coming months to secure winter stocks.
On July 25, Gazprom says it will further cut the supply to about 20 percent of the pipeline's capacity due to the "technical condition" of one of the turbines.
The German government says there is "no technical reason" for the move.
On July 30, Gazprom suspends gas supplies to EU and NATO member Latvia, citing violations of the conditions of purchase.
