Heavy rain triggered floods and landslides in the northern Indian state of Uttar Pradesh, killing at least 56 people over the past three days, a government disaster agency said on Sunday.

Uttar Pradesh, India's most populous state with more than 240 million people, is frequently battered by rain and thunderstorms during the annual monsoon season from June to September.

The latest deaths were reported during a spell of "exceptionally heavy rain that has affected much of Uttar Pradesh", the Relief Commissioner's office said in a statement.

More than 1,000 houses were damaged after "a depression over the Bay of Bengal moved inland and intensified rainfall across the region", it said.

India's weather office has warned in recent years of an increase in extreme weather events, including intense thunderstorms and lightning, which experts link to rising temperatures and changing climate patterns.

The statement said the state recorded 66.5 millimetres of rain between Friday and Sunday, compared to the season average of 7.6 millimetres.