Eighty groups sign letter to Ban Ki-moon insisting it is ‘critical to secure the service of a highly qualified humanitarian leader’

Efforts by David Cameron to parachute his former health secretary, Andrew Lansley, into a plum United Nations role have met with furious opposition from numerous of the world’s leading international disaster-relief organisations.

More than 80 of the world’s most important NGOs, including Oxfam, Save the Children and Christian Aid, have signed a letter to the UN secretary general, Ban Ki-moon, that implicitly criticises the appointment of a politician without long-standing experience of humanitarian crises to the role of emergency relief coordinator, a position currently held by the UK’s Baroness Amos.

The letter, seen by the Observer, says: “At a time of proliferating humanitarian crises, we believe it is critical to secure the service of a highly qualified and experienced humanitarian leader who can work with our organisations to ensure ... initiatives generate meaningful change, whilst also effectively representing the interests of millions of people affected by crises globally.”

Cameron’s support for an international role for Lansley was revealed in an exchange of letters late last year. The former health secretary and leader of the House of Commons wrote to the prime minister: “I am grateful to you now for expressing your support to me to take such a role in international public service in the months ahead.”

Cameron replied: “You have much more to give in terms of public service, and I look forward to being able to support you in doing so in the months and years ahead.”

The NGOs’ letter calls for the UN secretary general to establish a panel of experts to help him select the candidate – a move that would stymie Lansley’s hopes of landing the job.

The prime minister is thought to be determined that a Briton will retain the role after several key UN positions recently went to people from other European member states. However, Lansley is up against some strong candidates, including Germany’s Martin Kobler, currently the head of the UN’s mission in the Congo.

Lord Malloch-Brown, a former UN deputy secretary general and a crossbench peer, has warned against Lansley’s appointment, suggesting it would be an “act of great cynicism to allow someone who does not have background”.

Some 6,000 people have signed a petition against Lansley’s appointment posted by Avaaz, the online campaigning organisation.

“Victims of wars and natural disasters need an experienced leader to run the global system they rely on for survival,” said Sam Barratt, campaign director at Avaaz.

“Cameron’s choice of Lansley simply couldn’t be worse and thousands of people are calling on Ban Ki-moon to hire on merit, not nationality. It seems the closest Lansley has ever been to a disaster zone is the one he left behind in the Department of Health.”