Ukrainian President Viktor Yushchenko said there was "no alternative" to his country eventually joining NATO and want for the first time that Russia should be included in negotiations on the issue.
Yushchenko also vowed that Ukraine would "guarantee" that all Russian natural gas shipped to Europe through Ukrainian territory would reach its intended recipients, moving to calm Western concerns over another energy dispute.
"Ukraine has no other option -- no alternative exists" to NATO membership to ensure its national sovereignty, Yushchenko said on Thursday in an exclusive interview to AFP in Kiev.
"We must hold negotiations with all parties who are interested, or not interested, in Ukraine moving closer to NATO," the Ukrainian president said, clearly alluding to Russia which is fiercely opposed to Ukrainian membership in the alliance.
His comments came two days after NATO backed away from placing Ukraine and another ex-Soviet republic, Georgia, on a fast track for membership in the alliance despite strong US lobbying for this in recent years.
NATO also agreed at its ministerial meeting in Brussels on Tuesday to renew its dialogue with Russia, suspended following the brief war last August in Georgia, a move welcomed by Moscow as a return to a "position of realism."
Yushchenko, who has led the drive in recent years to disengage Ukraine from Moscow's influence and place it firmly on course for integration into key Western institutions, repeated his view that NATO membership represented no threat to Russia.
"If third parties are needed to provide international guarantees" that would help assuage Russia's concerns about NATO taking in Ukraine as a member "we are prepared for this," he said.