International development agency Oxfam says funds for the United Nations Pakistan disaster appeal are drying up and threatening millions of lives.

The DEC Pakistan Floods Appeal is now one of the three most generously supported appeals the charity has run in its 45 year history after the 2004 tsunami and the Haiti earthquake.

Arms companies including BAE Systems are facing sharp criticism for the growth of robotic weapons that allow operators to kill people thousands of miles away.

Of the 20 million people affected by the floods in Pakistan, some 85 per cent are women and children, and around 500,000 are pregnant women.