NATO delayed a decision on Ukraine's accession to the NATO Membership Action Plan, a key step toward joining the alliance, at a summit in Bucharest in spring, mainly over German and French opposition. However, the bloc pledged to review the decision in December.
"A statement was made in Bucharest, and I will reiterate it, that Ukraine will become a NATO member," Merkel told reporters after a meeting with President Viktor Yushchenko.
"Countries outside NATO have nothing to do with this issue, and should not discuss it," Merkel said, in an apparent reference to Russia, which has fiercely opposed Ukraine's accession to the Western military alliance.
Moscow has threatened to target its missiles at Ukraine if the country joins the bloc, whose ongoing enlargement closer to Russia's borders is seen as a security threat in Russia. In June, Russia's parliament recommended that the president scrap the friendship and cooperation pact Ukraine if it secures NATO membership.
Opinion polls in the ex-Soviet state have shown that the majority of Ukrainians oppose NATO membership. The NATO naval exercise underway near Ukraine's Black Sea port of Odessa has been accompanied by protests by opposition groups and locals.
During her first visit to Ukraine as chancellor, Merkel met with President Yushchenko and Prime Minister Yulia Tymoshenko, also focusing on the country's integration into the European Union and energy contacts, according to the presidential press office.