"The contribution from international creditors will not change," government spokesman Steffen Seibert told a regular briefing, noting that the €10 billion ($13 billion) package was "already very large".
Cypriot President Nicos Anastasiades said Friday he would appeal to EU chiefs for more help, a day after it emerged that the total cost of its EU-IMF bailout has surged to €23 billion from €17.5 billion previously.
That means Cyprus will now have to find €6.0 billion more than the €7.0 billion mooted in a preliminary agreement reached on March 25 in order to secure an EU-IMF contribution of €10 billion.
The news appeared to boost the teetering economy's danger of collapse and further threatened big bank deposits.
Anastasiades said he had already spoken to European Union Economy and Euro Commissioner Olli Rehn ahead of a key meeting of eurozone finance ministers in Dublin later Friday that is due to finalise the bailout terms.
He said he would also write to European Commission chief Jose Manuel Barroso and to EU President Herman Van Rompuy but did not specify what additional support he was seeking.
A Cypriot source in Dublin said that Nicosia was not seeking "extra money" from its eurozone partners but was instead looking for help from a European Commission
task force to lessen the burden of measures agreed in exchange for loans.
Under the preliminary bailout terms agreed last month at talks where Germany played a key role, Cyprus committed to drastically downsizing its once lucrative banking sector, raising taxes, reducing the public sector workforce and privatising state-owned utilities.