Pakistani volunteers from the Falah-i-Insaniat Foundation use a boat to rescue flood-affected residents from a village on the outskirts of Multan, in the central Punjab province on Tuesday.

AFP

Emergency workers battled on Tuesday to reach hundreds of thousands of people marooned by floods in India and Pakistan that have claimed more than 400 lives, as anger grew over the speed of the rescue effort.

The army said it was airlifting boats to the worst-hit areas of Indian Kashmir, where whole villages have been submerged and an estimated 400,000 people are stranded in the region's worst flooding for half a century.

"The situation in Kashmir Valley is still very grim, it is quite critical," said Rajesh Kumar, police Inspector General of the Jammu region in India's Jammu and Kashmir state.

"I don't know how many exactly, but there are many stuck in neck-deep water and need help as soon as possible," he said.

But with large parts of the state - including the capital Srinagar - underwater, rescuers were struggling to find enough vessels to ferry stranded people to safety.

State government official Rohit Kansal told the Press Trust of India news agency (PTI) that 100 boats being airlifted from Delhi would arrive shortly.

But many Srinagar residents said they were left to fend for themselves in the fast-flowing floods when rescue workers failed to arrive.

One man was seen hanging precariously from a rope strung from one side of the raging waters to another - his only way of getting across.

Another, retired college teacher Abdul Latif Rather, said he and his wife had waited hours for help on Sunday as the waters engulfed their home.

Local boys eventually came to their rescue with a makeshift raft and ferried them out to safety.

"They risked their own lives to get us," Rather said as he sat on the roadside near his flooded home.

"The entire (state) administration is a failure, is a disaster."

Indian authorities said the death toll from the floods was around 200 people. Some 400,000 people remain stranded mainly in Srinagar and south Kashmir, PTI quoted local officials as saying.

"There are still a few hundred thousand stranded in Srinagar (alone). About 60-70% of the city is flooded," Jammu divisional commissioner Shantmanu said.

In neighbouring Pakistan the number of dead stood at 206, with most killed in Punjab province, officials have said.

In one Pakistani village alone, close to the de facto border with Indian Kashmir, 125 houses have been destroyed, an AFP reporter at the scene said.

Thousands of troops, police and other emergency personnel have been deployed in both countries to deliver drinking water, blankets and other relief supplies using helicopters and boats.

At a wedding hall on Srinagar's outskirts, some 400 people gathered on the floor in small groups, taking stock of their lives after floodwaters submerged their homes.

"Everything happened so fast. The waters came rushing and we didn't have time to pack anything," Ruqsat Banu said as she comforted her elderly in-laws.

"The (rescue workers) were prioritising people, they were taking the women and the children but the men were left behind," said Banu, who had to leave without her husband.

"We don't know if he is all right, what has happened to him," Banu said. "We lost everything."

Banu, who is in her mid-20s, arrived on Sunday at the hall in Sanatnagar where residents have been drawn since days of heavy monsoon rains flooded the Jhelum river.

Locals who run the Sir Mohammed Iqbal hall, one of the few refuges with electricity, were busy serving food to victims, while others were stockpiling bandages and basic medicines in a corner.

"I've never seen anything like this in my lifetime. It's unprecedented, everything is underwater," 70-year-old S. Nabi said as he watched the chaos around him.

The military has stepped up its rescue efforts, with 42,500 people evacuated so far and 61 planes and helicopters pressed into action, the defence ministry said.