BRATISLAVA (Reuters) - Slovak opposition leader Michal Simecka accused Prime Minister Robert Fico of laying the ground to take the country out of the European Union as he launched an attempt to dismiss the leftist-nationalist government in a no-confidence vote on Tuesday.

The opposition effort looked set to fail as the government's slim majority in parliament was expected to back Fico.

Fico has sought to maintain relations with Russia in the Ukraine conflict and halted official military aid to Kyiv. He has criticised sanctions on Russia and escalated a rift with Kyiv after Russian gas supplies through Ukraine stopped at the end of 2024.

Fico, leader of the leftist Smer-SSD party and a four-time prime minister, has also said Slovakia needed to prepare for "all possible crisis situations" which the EU could face in the short term, suggesting even a break-up of the bloc.

"This cannot be read in any other way than... what we had warned of: that the government of Smer is preparing the ground for leading Slovakia out of the European Union," Simecka, leader of the Progressive Slovakia party, told parliament.

"I see this as such an existential threat to our national interests that we do not need anything else to declare no-confidence."

The government issued a statement ahead of the no-confidence vote which said it was sticking with its policy manifesto declaring EU membership as irrevocable but reserving the right for criticism. Fico was expected to speak later on Tuesday.

Fico travelled to meet Russian President Vladimir Putin in Moscow on a unannounced private trip in December to discuss gas and Ukraine. A delegation of several government members of parliament went to Moscow last week seeking improving ties.

He has since accused the opposition of preparing popular protests with the aim of seizing power, which the opposition has denied.

Fico's government has never officially cast doubt on EU or NATO membership but Fico has travelled to Russia, China, Brazil, and Turkey to forge ties under what he calls a foreign policy in all directions.

Fico's cabinet was expected to be backed by Smer as well as deputies from the nationalist SNS and centre-left Hlas party, giving him enough votes. However, Hlas has rejected any discussion over EU membership, and several of its deputies have protested against Fico's foreign policy.

(Reporting by Radovan Stoklasa and Jan Lopatka; Editing by Ros Russell)