"Today I have offered my resignation to the president of the republic," Fico said. "If the president accepts it, I am ready to resign tomorrow."
Read more: Mafia ties and journalist's murder threaten to bring down government
The shock announcement is seen as an attempt by the embattled prime minister to keep his three-party coalition in power and avoid snap polls.
"Early elections would be almost certainly accompanied by chaos and instability," Fico said.
Brutal killingFico's government has been plunged into crisis following the murder of Slovak journalist Jan Kuciak and his fiancee in February. The 27-year-old reporter had been investigating high-level corruption and alleged Mafia links to politicians and businessmen in Slovakia.
Read more: Opinion: Warning signal for Europe from Slovakia
The killings reignited debate about corruption and press freedom in Slovakia, triggering mass anti-government demonstrations across the country. Protesters also demanded Fico's government step down and hold early elections.
Police have interviewed more than 100 people as part of the investigation into the deaths, but no one has yet been charged.
Political crisisSlovakia's opposition had called for a no-confidence vote to be held against Fico's government next Monday.
Earlier this week, a junior partner in the Fico-led coalition, the Most-Hid party, threatened to leave the alliance unless fresh elections were held. President Andrej Kiska has also called for sweeping changes, or early elections, to solve the crisis. But Fico has rejected the idea of polls, saying the country could "plunge into chaos if the current opposition takes power."
It was not immediately clear if Kiska would agree to the terms of Fico's resignation.
nm/jm (AP, Reuters)
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