UPDATE 1-Greece says expects decisions from Eurogroup on debt

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ATHENS, June 20 (Reuters) - Greece said on Wednesday it expected euro zone finance ministers to take decisions on Thursday outlining "substantive" measures to render the country's debt sustainable.

Government spokesman Dimitris Tzanakopoulos also said there was no truth in speculation that a deal settling a name dispute with neighbouring Macedonia was tied in any way to Greek debt relief.

"We are optimistic that we are on the verge of a solution with substance, which will have a multiplying effect to the already noted momentum of the Greek economy," Tzanakopoulos told a news briefing.

"The accepted criteria for all sides is that this solution be convincing for markets and embed the creditworthiness of our country, the final act in restoring the credibility of Greece to be able to plan for the next day like any ordinary country."

Euro zone finance ministers will discuss debt relief for Greece on Thursday to ensure the country can return to market financing after eight years of loans from euro zone governments and to enable sustained economic growth.

Athens is set to formally exit a bailout programme in August, the third for the indebted country which first sought external aid in 2010.

EU officials have repeatedly said Thursday's meeting will be crucial to seal Greece's financial future, as decisions will need to be made on the use of about 40 billion euros that remains unspent under the 86 billion-euro bailout programme which expires on Aug. 20. (Reporting by Renee Maltezou and George Georgiopoulos Editing by Alison Williams)