Poland and Ukraine said Wednesday they would take legal action against Russian plans for a second gas pipeline to the EU, a project they allege Moscow could use for political "blackmail".
Russian energy giant Gazprom plans to build a pipeline called Nord Stream 2 under the Baltic along an existing line to boost gas delivery capacity to Germany from Russia, thus bypassing Ukraine and Poland.
"For many years we've said that both Nord Stream I and Nord Stream II are political tools, used above all by Russia on Europe... Russia can use these two lines for blackmail at any time," Polish Foreign Minister Witold Waszczykowski said at a joint press conference in Warsaw with Ukrainian counterpart Pavlo Klimkin.
Waszczykowski also said that his country, a member of the European Union, and Ukraine, which is not a member of the EU, would "probably join forces" to use all legal means including international courts to convince the EU about the pipeline's alleged "political" nature.
"Our opinions on cooperating with Russia and on energy security differ from views held by many western European states," Waszczykowski said, adding that he thought Western views were "naive".
Under Moscow's thumb during the communist era, Warsaw and Kiev have long lobbied for energy independence from it, arguing that Russia could turn off the tap on gas supplies to press client states into complying with its wishes.
Klimkin said the EU ought to ask itself whether it wants to be "dependent on another state, because Gazprom is part of the Russia that nobody trusts."
Waszczykowski said that thanks to its new Baltic LNG terminal and new deliveries via a pipeline from Norway, Poland would be able to wean itself off Russian natural gas within five years.
"We have limited confidence... in European institutions," he said, adding Poland was doing its all to be "free from the diktat" of relying on gas deliveries from Russia.
Klimkin said that Ukraine halted gas purchases from Russia more than a year ago. Moscow seized Ukraine's Crimea region in 2014 and has since backed a separatist insurgency in the east of the country.
A peace plan brokered by France and Germany in February 2015 to end the conflict in Europe's backyard has stalled and bloody clashes continue regularly along the frontline.
Waszczykowski on Wednesday suggested that "sooner or later" the United States would have to become involved in brokering a lasting peace.