EU leaders are to hold emergency talks in Brussels on the Mediterranean migrant crisis.
Government sources told dpa that the Greek reform programme would form the core of the Merkel-Tsipras meeting.
Tsipras' cash-strapped leftist government is under pressure from fellow eurozone members and the IMF to present details of reforms needed to unlock some €7.2 billion in bailout funds.
On Friday, eurozone finance ministers will meet in Latvia's capital Riga to discuss Greece's economic programme.
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