A "red alert" has been issued for almost all of Belgium, due to high temperatures

Official meteorologists registered a record high temperature for Belgium on Wednesday as western Europe sweltered under a heatwave that has disrupted transport and triggered safety warnings.

David Dehenauw, chief forecaster at the Royal Meteorological Institute, said Thursday that a high of 40.2 degrees Celsius (104 Fahrenheit) had been recorded the day before in the eastern city of Liege -- the highest ever since records began in 1833.

Due to the high temperatures, the institute issued a "red alert" for almost all of Belgium -- except the North Sea coast -- through Friday.

In Brussels on Thursday the Royal Meteorological Institute measured 34.2 degrees at noon (10:00 GMT), where Wednesday's 35.7 degrees looked set to be exceeded in the afternoon.