WARSAW, Dec 15 (Reuters) - Poland"s daily death toll from COVID-19 during the fourth wave of the pandemic has climbed to a record 669, the health ministry said on Wednesday, as the country battles high infection rates with tighter restrictions. "This is the effect of these last weeks, when the number of cases has accumulated. They are mainly unvaccinated people," government spokesman Piotr Muller told private broadcaster Radio Zet earlier. The health ministry also said there were 24,266 new COVID-19 cases. Poland"s highest daily death toll during the pandemic overall stands at 954, hit in April this year. Poland imposed new regulations on Wednesday to curb the spread of the virus, further limiting numbers in some public spaces such as restaurants and closing nightclubs. Countries around the world are tightening restrictions ahead of the festive season following the emergence of the new fast-spreading Omicron variant last month, which has now been detected in 77 countries. "There is no doubt that Omicron is already in Poland ... Within the EU, we have free movement of people, so it is obvious that this mutation should be in Poland," Muller said.