(Reuters) - Slovak Prime Minister Robert Fico said on Thursday his administration would plan preventive measures around public protests that state officials have said risk escalating into attempts at overthrowing the government.

Fico has said opposition groups plan to escalate protests, including through the occupation of government buildings and forcing the fall of the government.

Citing information from intelligence services, Fico reiterated accusations, without showing evidence, that there was a group of unidentified experts in Slovakia that had helped in protests in Ukraine in 2014 and Georgia last year.

The planned protests were aimed at creating chaos, possibly including confrontation with police, he said.

"The situation is serious," Fico told a televised briefing after a meeting of the State Security Council that he chairs and which tasked the government with planning preventive measures.

"We see a structure that it trying to attack the constitutional setup of the Slovak Republic," he said.

The civic groups organising protests as well as the opposition have firmly rejected Fico's accusations.

The main opposition party Progressive Slovakia has called them delusions meant to silence it and also cover cracks within his three-party coalition and its failures to address the country's economic and social problems.

Fico and his leftist-nationalist government have stepped up attacks against the liberal and conservative opposition since he survived an assassination attempt last year.

Public protests in the small central European country have grown since Fico returned as prime minister for a fourth time in 2023 amid worries over his government weakening democratic values and shifting its foreign policy away from EU and NATO allies and closer to Russia.

Another protest was planned for Friday.

(Reporting by Jan Lopatka and Jason Hovet in Prague; Editing by Alex Richardson, William Maclean)