The Sri Lankan government is paying a top British PR firm about £3m ($4.7m) a year to try to enhance the country's post-war image, the BBC understands.
Bell Pottinger Group was recently hired to lobby UK, UN and EU officials.
The government says it employs several PR companies but will not disclose their names or the amount paid. Bell Pottinger also refused to give details.
Sri Lanka's authorities strongly deny alleged human rights abuses in the defeat of Tamil Tiger rebels last year.
Bell Pottinger - whose motto on its website is "Better reputations, better results" - is believed to be lobbying on Sri Lanka's behalf in Brussels, following an EU decision to withdraw special tax concessions called GSP Plus.
The European Union decided in July to withdraw Sri Lanka's preferential trade access to EU markets, saying it had failed to improve its human rights record.
It is thought the firm was also employed in Sri Lanka's attempts to prevent the UN secretary general appointing an advisory panel on alleged war crimes committed during the civil war.
In the UK, the group's main focus is countering what the Sri Lankan government says is propaganda by pro-Tamil Tiger groups in the influential Tamil diaspora.
Last week the firm helped promote the UK visit of Sri Lankan Foreign Minister Prof GL Peiris, who gave the keynote speech at London's International Institute of Strategic Studies.
Sri Lanka's Central Bank Governor Ajith Nivard Cabraal confirmed that the government had hired a few PR companies. But he refused to reveal the amounts paid.
"So many people are spending huge sums of money to tarnish our country's image. Media institutions are also involved in this. We will do everything possible to boost that image and I believe it is our duty," he told the BBC.
A Sri Lankan government source, who did not want to be named, confirmed to the BBC that the amount paid to Bell Pottinger was in the region of £3m this year.
Sri Lanka's image abroad - and in the UK in particular - has much resting on it. Britain is the main provider of tourists to the country from outside the South Asia region.
Sanjika Perera, the UK Director of Sri Lanka Tourism Promotion Bureau, said: "Arrivals from the UK are up 30% year on year and the market sentiments/forward bookings indicate that UK will pass the 100,000 mark in arrivals in 2010."
Tourism promotion in the UK is handled by two other PR firms, Representation Plus and Romanski.
When a request was made under the Freedom of Information act, the chairman of Bell Pottinger's parent company, Chime Communications, told the BBC Sinhala service that the act only covers UK government departments and certain contractors.
"Further I must tell you all our client contracts are commercially confidential - consequently we cannot supply the information you seek," Lord Bell said.