BERLIN, May 26 - Europe's Energy Commissioner said on Monday Ukraine and Russia had made further progress in a dispute over gas prices and his proposal that Ukraine to pay $2 billion of back debt by Thursday could pave the way for further talks on Friday, Reuters reported.

Speaking after three-way talks with Russia's and Ukraine's energy ministers, Guenther Oettinger said the two governments would study his proposal that Ukraine pay Russia $2 billion by Thursday and a further $500 million by June 7.