Landslides and flash floods triggered by heavy monsoon rains have killed nearly 300 people in northern India and Pakistan, officials said today.

Five days of incessant rains in Indian-controlled Kashmir have left at least 120 people dead in the region's worst flooding in more than five decades, submerging hundreds of villages and triggering landslides, officials said.

In neighbouring Pakistan, more than 160 people have died and thousands of homes have collapsed, with an official saying the situation was becoming a "national emergency".

Rescuers in both countries were using helicopters and boats to try to reach tens of thousands of people stranded in their homes as floodwaters rose and submerged many villages.

Rescue efforts in Srinagar, the main city in Indian Kashmir, were hampered by fast-moving floodwaters that submerged large parts of the city.

The rains had stopped today but officials said the spreading water from the overflowed Jhelum river was moving too fast to allow boats to reach many people stranded in Srinagar.

By evening, several boats had been deployed to start rescue efforts, said Omar Abdullah, Jammu and Kashmir state's top elected official.

In many of Srinagar's neighborhoods, the water was about 12ft deep, submerging entire houses. Stranded residents left their homes to move in with friends or relatives in safer areas.

Floodwaters entered the first floor of the state's main maternity hospital, forcing more than 200 patients and attendants to move to higher floors of the building.

Thousands of police officers and army rescue workers were fanned out across Jammu and Kashmir to help with relief and rescue efforts.

Indian prime minister Narendra Modi surveyed the flood-hit areas from a helicopter and promised the state federal help to deal with the devastation, which he described as a "national level disaster".

Across Indian Kashmir, at least 450 villages have been submerged and 2,000 others have been affected by the floodwaters, officials said.

All schools, colleges and offices have been shut, and electricity and drinking water supplies have been limited across the state.

In Pakistan, 103 people have died in the eastern province of Punjab from the collapse of houses, flooding and electrocution, said Ali Imam Syed, a senior official in the province's rescue agency.

He said more than 5,000 people had been rescued since Thursday, adding that three soldiers had gone missing during the rescue operation.

Ahmed Kamal, spokesman for Pakistan's National Disaster Management Authority, said 48 people had died in the Pakistani-administered part of Kashmir and 11 in the adjacent Gilgit Baltistan area since the flooding began.

"Army helicopters and navy boats are rescuing people and taking them to safety from submerged villages in Punjab and affected areas of Kashmir," Kamal said.

He said that the flooding had hit 286 villages in Punjab as several rivers breached their banks and that the crisis was rapidly becoming a "national emergency".

More than 4,000 homes across Pakistan have collapsed, rendering thousands of people homeless.

Pakistan's armed forces and civilian rescuers have mounted a massive operation using helicopters and boats to get villagers to safety. Mr Kamal said 95 relief camps had been set up for those displaced by the flooding.

Kashmir is divided between India and Pakistan, but claimed in its entirety by both countries.