SOFIA, Jan 11 (Reuters) - Bulgaria"s prime minister, president and senior ministers have gone into precautionary self-isolation after a participant at a security meeting they attended tested positive for the coronavirus, a health official said on Tuesday. Chief health inspector Angel Kunchev said all participants in the consultative National Security Council on Monday were in good health but would remain in self-isolation after Parliament Speaker Nikola Minchev tested positive. Along with Prime Minister Kiril Petkov and President Rumen Radev, the meeting was attended by the ministers of interior, defence and finance and senior members of the main political parties. They met to discuss Bulgaria"s position towards North Macedonia, deciding that lifting Bulgaria"s veto on the start of Skopje"s EU accession talks should not be rushed but linked to results. Petkov had planned to visit North Macedonia on Jan. 18 but the trip may now be rescheduled. "The prime minister will be under quarantine as are the rules," a government press official told Reuters. "There will be a visit to North Macedonia, and we will inform you once a new date is set." Petkov will continue his work remotely while his duties that require attendance will be taken over by deputy premier Kalina Konstantinova, the government said. Bulgaria has experienced a spike in coronavirus infections recently as the Omicron variant spread in the European Union"s least vaccinated member state. On Tuesday, the country of 7 million people reported 6,761 new cases and more than 800 people were taken to hospital. The pandemic has caused 31,672 deaths. The officials and politicians who attended the meeting on Monday may stay in quarantine for up to seven days after the health ministry changed the rules for self-isolation, effective from Jan. 11. The quarantine for contact people with full vaccination and a booster dose can be lifted earlier if they present a negative PCR test 72 hours after being ordered to isolate. Kostadin Kostadinov, leader of the ultra-nationalist Revival party and a vocal anti-vaccine activist who also attended the security meeting, said he tested negative for coronavirus on Tuesday and questioned the need to be quarantined. His party, which has called COVID vaccines "experimental liquid", is organising a protest on Wednesday against the obligatory health pass for entry to many indoor venues, including shopping malls and cafes.