UK ministers have been accused of spending British aid money on a public relations campaign to promote water privatisation in Sierra Leone.
The World Development Movement (WDM) claims the Department for International Development advertised for a company to advise on privatising state companies.
WDM says the international consultancy firm was being asked to promote privatisation in the African state.
The government said it was responding to a call for help from Sierra Leone.
A spokesman from international development ministry (DfiD) said Sierra Leone had asked for international support to advise on reforms that could boost the economy, investment and reduced the financial burdens on the government.
"DfID does not force developing countries to privatise their water or any other service as a condition for the receipt of aid. That is a matter for individual governments," the spokesman added.
"DfID spend on consultants has fallen from 10% of the total aid programme in 1997 to 5% last year."
Failing to deliver?
WDM has asked ministers to declare the value of the PR contract and has queried its legality.
The organisation plans to write to any short-listed companies requesting their withdrawal from the bidding process.
WDM policy officer Vicky Cann said: "Time and again throughout the world water privatisation has failed to deliver clean water to poor people.
"Now we find out that in the poorest country in the world, which is still recovering from a decade long bitter civil war, DfID is not only going to pay international consultants to advise on how to privatise water in Freetown, but they will also pay for a propaganda campaign to run alongside it to counter public resistance.
"Is this really the best use of UK aid money - UK taxpayers' money - that DfID can come up with? As far as we are concerned this is definitely immoral; the legal advice that we have is that it could well be illegal too."
Lib Dem international development spokesman Andrew George warned a similar scheme to privatise water in Tanzania had ended in "scandalous" failure.
"Ministers should ensure developing countries can make genuine choices about service provision. Privatisation should be just one of a number of options available to Sierra Leone and other poor countries," he said. "The first priority, for a fragile economy, should be aid and development assistance."