More helicopters are urgently needed to deliver aid to the millions of Pakistanis still cut off by devastating floods, the United Nations World Food Programme says.
Many roads have been blocked and bridges washed away by what UN Secretary-General Ban Ki-moon has called a "slow-motion tsunami".
Millions of people need food, shelter and water after weeks of floods that have submerged much of the country, affecting about a fifth of the population. The death toll is about 1600.
Tens of thousands of villages remain underwater and there are warnings the crisis may worsen as floodwaters continue to surge south along the Indus River.
The BBC reports aid agencies as saying that funding for relief operations is increasing but that much more is needed.
Experts have warned that greater relief efforts are needed to avoid a second wave of deaths from waterborne diseases such as cholera.
A spokeswoman for the World Food Programme, Emilia Casella, said on Friday that the agency only had 10 helicopters at its disposal but expected to have another five later in the day.
She said it was not enough: "If you do the math, we are trying to reach six million people and today we've reached 1.2 million."
Pakistan has accepted an offer of about $US5 million of flood relief aid from India. Foreign minister Shah Mehmood Qureshi says the offer was a welcome initiative.