Firefighters in Spain, Portugal and Greece battled ongoing wildfires Friday, an important religious holiday in all three countries, as persistent hot, dry conditions challenged efforts to contain the blazes.

Portugal suffered its first death Friday from the fires raging there, as Spain's weather agency warned of a "very high to extreme risk" of more wildfires there during Europe's intense heatwave. Further east, Greece was still fighting blazes on one Aegean island, but the situation had improved for several other southern European countries.

Authorities warned of "unfavourable conditions" to tackle flames that have already killed seven people and burned an area the size of London.