United States Treasury Secretary Jack Lew called Greek Prime Minister Alexis Tsipras on Friday to express support for a favourable outcome in Greece's negotiations with its euro zone partners, Tsipras' office said in a statement on Friday.

Tsipras told Lew that Athens is intent on reaching a deal with its partners on a new support program that will put an end to austerity and pursue necessary reforms, his office said.

"Mr. Lew noted the support of the U.S. ... and the importance such a development would have for financial stability in Europe," the statement said.

The Greek government has promised to do "whatever we can" to secure a deal with its international creditors next week, as experts from both sides held technical talks on Friday to lay the ground for an agreement.