Karel De Gucht said an international peacekeeping mission should take over from Russian forces in Transdniester to facilitate a solution to the 16-year dispute Moldova and Transdniester.
After talks in Tiraspol with separatist leaders, De Gucht also said that Transdniester should return to negotiations mediated by the international community without imposing conditions.
De Gucht, who also called on Transdniester to respect human rights, said it would be "illogical" to set terms for talks held under the auspices of Russia, Ukraine, the OSCE, as well as the European Union and the United States.
Separatist leader Igor Smirnov later told the media that Transdniester would only return to the negotiating table if new customs regulations imposed earlier this year by Moldova, Ukraine, and the European Union are abolished.
After the talks, De Gucht headed for the Ukrainian city of Odessa, where he is scheduled to meet with Ukrainian Foreign Minister Boris Tarasyuk.
De Gucht is then due, on June 2, to travel to Kyiv.
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