However, veteran Turkish Cypriot leader Rauf Denktash, unhappy about the concessions the plan demands, said on Wednesday he would not attend the Swiss talks, though his pro-settlement prime minister, Mehmet Ali Talat, is expected to go.
A Greek Cypriot government spokesman on Thursday said Denktash's decision raised doubts about the Turkish Cypriots' commitment.
"This must be carefully assessed so there are no further complications. But it does raise substantive procedural problems and its significance to negotiations must be examined," he said.
In the sign of a growing gap between Denktash and his traditional backers in Ankara, Turkish Foreign Minister Abdullah Gul tacitly chided Denktash over his stance.
"We must all work day and night, thinking of the Turkish Cypriots' future. We won't get anywhere with heroic speeches on these subjects," he told reporters in Ankara
"We won't get anywhere with heroic speeches on these subjects"
foreign minister, Turkey
Greek and Turkish Cypriot leaders have so far made little progress on their own in the talks, aimed at reuniting the east Mediterranean island on the basis of a United Nations peace plan before it joins the European Union on 1 May.
Under a tightly-scripted UN timetable, officials from the 'motherlands' Greece and Turkey will attend the talks after 22 March. Greek Prime Minister Costas Karamanlis and Turkish Prime Minister Tayyip Erdogan will then join in from 28 March 28.
UN Secretary-General Kofi Annan will fill in any gaps left in the plan which goes to a pan-Cyprus referendum on 20 April.
Diplomats said the planned personal involvement of the Greek and Turkish leaders underscored their determination to resolve a problem which has bedevilled bilateral relations for decades and which could still wreck Turkey's own hopes of joining the EU.