Oxfam is warning of the difficulties aid agencies will face in tackling the humanitarian crisis following the start of the war in Iraq.
Many are reliant on UN food
The United Nations is estimating up to two million people could be forced to leave their homes when the bombing begins.
Oxfam outlined their plans to tackle the crisis at a news conference in London, but warned that the task would be made more difficult if all of Iraq's neighbours did not open their borders. It is already setting up camps.
Director Barbara Stocking said: "We may need to scale up very quickly to deal with big numbers.
"It will be possible to do so, though it would need a lot of money.
"The governments of some countries, Syria and Jordan for example, are saying that they will take refugees, while others are proving more difficult, Turkey for example, but we don't know what the final decision will be.
If you hit power stations and pumping stations... cholera and typhoid can spread like wildfire
"We want all the borders to be open to refugees."
Kate Allen, UK director human rights organisation Amnesty International, said: "In the last conflict in the Gulf there were two and a half million refugees.
"We want to see that protection is afforded to these people."
Ms Stocking said attacks on pumping stations and power plants by UK and US forces could help spread disease in Iraq and breached international rules on warfare.
She argued under Geneva conventions, objects indispensable to civilian life could not be attacked.
"If you hit power stations and pumping stations, you stop water and sewage pumping, and you don't just get unpleasantness, but danger to life, cholera and typhoid can spread like wildfire."
Cluster bombs, also criticised during the war on Afghanistan, are again a target for pressure groups. The government is again extremely unlikely to offer any pledge about restricting their use.
Ms Allen said the bombs leave unexploded "bomblets" over a wide area, which
can detonate at the slightest touch.
Child mortality is high in Iraq
"They lie there and then cause maiming and destruction of life for years after the conflict," she said.
"They are just like a landmine."
Ms Stocking offered her backing to International
Development Secretary Clare Short, who has decided not to follow through with her threat to resign over the war.
"Clare Short has been an excellent development
secretary. For us as a humanitarian agency, we think it's a good thing to have her there at this moment."
Ms Allen said: "The responsibility lies with each member of the British Cabinet to make sure humanitarian issues are at the centre of the debate.
"This is a country which, due to decades of misgovernment and a very harsh sanctions regime, is very vulnerable at the moment."