ANKARA (Reuters) - President Tayyip Erdogan said Turkey could not abandon its ties with Russia or Ukraine, and he criticised Western diplomatic efforts with Moscow as achieving little, broadcaster NTV and others cited him as saying on Wednesday.

       Speaking to reporters on a flight back from Africa, Erdogan repeated his offer to mediate between Russia and Ukraine and said NATO member Turkey, which has good ties with both, would take steps that do not harm its bilateral ties.

       "It is not possible for us to abandon either (country)," he was cited as saying by Turkish broadcasters. "Our aim is that we take such a step that, God willing, we sort this out without abandoning either one."

       He called on Ukraine and Russia to resume negotiations, and said NATO needed to "determine its stance" after the summit on Wednesday.

       Russian's recognition of two breakaway regions in eastern Ukraine this week has prompted swift backlash and sanctions from Western powers. Turkey, which borders both Ukraine and Russia in the Black Sea, is against sanctions in principle, but has called Russia's move unacceptable.

       (Reporting by Tuvan Gumrukcu; Editing by Jonathan Spicer)