European Energy Commissioner Gunther Oettinger said EU member states need to develop stronger partnerships in the energy sphere in order to avoid falling victim to "political and commercial blackmail."
Russia supplies about a quarter of the EU's gas needs, though most of those supplies run through the Soviet-era transit network in Ukraine. In 2009, Russian energy company Gazprom cut gas supplies through Ukraine because of contractual disputes and recent tensions over Ukraine's embrace of the West have added further strains to European energy security.
"We need to accelerate the diversification of external energy suppliers, especially for gas," Oettinger said in a statement. "Only concrete actions will help."
The EU said it spends more than $1 billion per day on energy imports. More than 60 percent of the region's gas supplies come from foreign suppliers, notably Russia, Norway and Algeria.
Members of the EU have looked to Azerbaijan for sources of piped natural gas as well as liquefied natural gas from the United States.
The EU said it would maintain its relationship with "reliable" energy partners, but look for new partnerships and alternate supply routes.