Extreme temperatures in Japan and the Korean peninsula have led to deaths and illnesses and affected day-to-day life, during a heat wave that South Korean President Lee Jae Myung has deemed a "national disaster."

Authorities issued a heatwave warning for all of Seoul on Tuesday while the city of Yangsan recorded 42.5 degrees Celsius on Sunday.

A deadly heat wave is setting temperature records in South Korea and complicating earthquake recovery efforts in Japan, where three lions have also died at a zoo.