Speaking at a press conference following an informal summit of EU leaders in Brussels on Thursday, Juncker said the talks would be aimed at avoiding a winter crisis situation.
Earlier this month, Russian Energy Minister Alexander Novak said that Russia is ready to discuss a summer gas agreement with Ukraine, as long as the talks include a clear schedule of Ukrainian debt repayment.
Kiev's debt forced Moscow to suspend gas deliveries to Ukraine for nearly six months in 2014. Deliveries resumed on December 9 under the so-called winter package deal, mediated by the European Union and signed by Russian energy giant Gazprom and Ukraine's Naftogaz in late October, 2014.
The deal stipulated that Ukraine repay $3.1 billion of its $5.3-billion gas debt to Russia before the end of 2014 and pay in advance for future gas supplies.
Russia has also granted Ukraine a temporary discount of $100 per 1,000 cubic meters under the winter package, which covers the cold winter season and expires on April 1, 2015.