"Such wars are not planned," Viktor Yushchenko told the Ukrainian paper Dilo.
Kiev and Brussels signed an agreement to modernize Ukraine's Soviet-era gas pipeline network last week, triggering an angry reaction from Russia, which exports most of its Europe-bound gas via Ukraine.
Moscow said earlier it had been deliberately excluded from the deal. It delayed inter-government talks with Kiev and threatened to review energy ties with the European Union if its interests continued to be disregarded.
The spat has stirred fears of a repeat of January's dispute between Russia and Ukraine, when European Union consumers were left without gas for about two weeks.
Yushchenko said as quoted by the paper that the agreement with the EU was designed to make exports more reliable and transparent.
Ukrainian Premier Yulia Tymoshenko has said on several occasions that Russia would have a full role in the modernization of Ukraine's gas grid.