Several European countries have issued heat warnings as a prolonged spell of high temperatures sweeps across the continent.

Spain's national weather agency said on Sunday that the first heatwave of the summer had spread across the Iberian Peninsula and the Balearic Islands and is expected to last through June 25. Temperatures in many parts of the country reached between 40 and 42 degrees Celsius that day.

The agency warned that outdoor activities around midday could pose significant health risks, particularly for older adults and people with cardiovascular conditions. The risk of wildfires is also expected to increase as temperatures remain elevated.

In France, authorities issued the highest-level red heat alert for Paris and 34 other departments on Sunday. According to the national weather service, the warning covers more than one-third of metropolitan France, with temperatures in some areas forecast to reach 41 degrees Celsius on June 22.

France's state-owned railway operator advised at-risk passengers to avoid train travel during the peak of the heatwave.

In Italy, meteorological data showed temperatures climbing to as high as 39 degrees Celsius in inland regions on Sunday. On June 19, the country's Health Ministry had issued red heat alerts for five cities, including Turin and Florence, due to severe heat conditions. By June 21, the ministry had expanded the number of cities under the highest heat alert level to eight as the heatwave intensified.

Meteorologists say large parts of southern and western Europe are expected to remain under unusually hot conditions in the coming days.