A heat wave has claimed two lives in Greece and killed six more people in Romania as temperatures soared to 46 degrees Celsius (114.8 Fahrenheit) in parts of southeast Europe.

Turkey and Cyprus also reported deaths blamed on the intense heat, while three people drowned in Bulgaria swimming in unsupervised dams and beaches at the weekend as temperatures climbed well above early summer averages.

Greece, which has seen some of the highest temperatures, is set to record its hottest ever June. The Greek government responded by ordering all public offices to work only half days on Tuesday and Wednesday, closing at midday to reduce energy consumption and allow people to stay out of the sun at the hottest time of the day.

Meteorologists said temperatures could hit 40 degrees Celsius in the Romanian capital Bucharest on Tuesday, the highest level in 90 years. Twenty-five people have died in Romania during the recent hot spell, health ministry data showed on Monday.

Forest fires were also reported near several prominent tourist spots on Turkey's Mediterranean coast.