BERLIN--Greece will get only get money from its international creditors once Athens has successfully completed the existing bailout program, the spokesman for Germany's finance minister said Friday.

Asked whether it was possible for cash-strapped Greece to receive some bailout money before Athens has completed the program of budget cuts and economic overhauls, finance minister spokesman Martin Jaeger said Germany sees no basis for an early payout of aid.

"What we are talking about is the payment of the last tranche and a successful completion of the program is mandatory for the payment of this last tranche," Mr. Jaeger said at a news conference.

German daily Sueddeutsche Zeitung reported Friday that Greek Prime Minister Alexis Tsipras had urged European Commission President Jean-Claude Junker to meet for talks on Greece's financial squeeze that has left the government unable to pay wages to all government employees. According to the daily, Mr. Juncker had rejected the request.

Last month, Greece and the eurozone reached an agreement for a four-month extension of its bailout from international lenders.

Under the agreement, Greece must present a detailed package of budget cuts and economic overhauls which is required to pass the scrutiny of the European Commission, the European Central Bank and the International Monetary Fund, the supervisors of the bailout.

Only after the implementation of these measures will Athens received the next 7.2 billion euros ($7.88 billion) slice of a EUR240 billion bailout that has kept the country afloat for almost five years.

Write to Andrea Thomas at Andrea.Thomas@wsj.com

Subscribe to WSJ: http://online.wsj.com?mod=djnwires