Eurozone finance ministers delayed the latest bailout disbursement to Greece on Wednesday awaiting clarification on a legal case against European experts who had worked on the Greek privatisation programme.

While officially approving the latest raft of reforms, eurozone finance ministers in a conference call put off the payment of 8.5 billion euros ($9.5-billion) from Greece's massive bailout.

The eurozone finance ministers  "encouraged the Greek government to resolve the pending issues swiftly," a statement from the European Stability Mechanism, the eurozone bailout fund, said in a statement.

This would "pave the way for the approval of the third tranche" from the country's 86-billion euro bailout, agreed in 2015.

Senior eurozone officials would  meet again by teleconference on Friday in hopes of releasing the funds, instead of Wednesday as originally planned, the statement said.

Eurozone ministers struck a long-delayed bailout deal with Greece on June 13 to unlock the badly needed rescue cash.

The deal was to avert a repeat of the summer of 2015 when Greece spectacularly defaulted on an IMF loan, and allow Athens to meet seven billion euros of debt repayments due in July.

But Spain last month threatened to block the disbursement, angry that Athens has failed to drop a legal case against European experts who had worked on the Greek privatisation programme.

Greece's supreme court on Tuesday dismissed the case, raising expectations that the last-minute snag would be quickly overcome.

"I think they will solve the last pending issues as discussions are about relatively small assurances," a source close to the matter told AFP on condition of anonymity.

"Nobody would like to get Greece back in trouble," the source added.

The legal case concerns three advisors from Spain, Italy and Slovakia to the Greek privatisation agency, created at the insistence of Germany in the wake of the debt crisis in 2011.

The Greek courts initiated proceedings against the experts in 2014 after alleged irregularities in the sale of 28 real estate properties owned by the Greek state.