The lightning bolt extended 477.2 miles across Texas, Louisiana and Mississippi in April 2020, the World Meteorological Organisation (WMO) said.

This beat the old record of 440.6 miles set in 2018.

Also in 2020, a single lightning flash over Uruguay and northern Argentina lasted 17.1 seconds. The previous record was 16.7 seconds.

Both regions are two of the few places in the world prone to the type of intense storms that can produce what are called "megaflashes", said Randall Cerveny of Arizona State University, head of records confirmation for the WMO.

He said lightning does not usually stretch further than 10 miles, and it normally lasts less than a second.

"These two lightning flash records are absolutely extraordinary," he said.

Both were cloud-to-cloud, several thousand feet above the ground, so no one was in danger, he added.

Both incidents have not been linked to climate change and were spotted and confirmed thanks to new satellite tracking technology.