The Greek finance minister says the country must reach an outline funding agreement with its lenders at a meeting of euro zone finance ministers on April 24.
The remarks come amid growing uncertainty on new bailout loan terms.
In an interview with a Greek newspaper, Finance Minister Yanis Varoufakis says the government wants to finish negotiations as soon as possible, but Greece will not accept terms that suffocate its economy.
Athens offered a new package of reforms last week in the hope of unlocking remaining funds from its bailout program, but its EU and IMF lenders have yet to sign up to the proposals.
Athens has not received bailout aid since August last year and will reportedly run out of funds on April 20th.
Varoufakis says Athens will make its 450-million euro payment due to the IMF by Thursday.