Spain on Friday warned of "very high or extreme fire danger in most of the country," as firefighters there continue battling 14 blazes in temperatures up to 104 degrees Fahrenheit.

By Michael Francis Gore, Charlie Devereux and Ana CanteroVILLANUEVA DE LA SIERRA, Spain (Reuters) -Spain battled 14 major fires driven by high winds and aggravated by heat on Friday as authorities warned of "unfavourable conditions" to tackle flames that have already killed seven people and burned an area the size of London.

A heatwave with temperatures exceeding 40 degrees Celsius, or 104 Fahrenheit, on several days this month was expected to last through Monday.

Scorching heat hampered efforts to contain 20 major wildfires across Spain on Sunday, prompting the government to deploy an additional 500 troops from the military emergency unit to support firefighting operations.