A Sri Lankan diplomat has launched an attack on Callum Macrae, the filmmaker behind Sri Lanka’s Killing Fields, threatening to bar him from entering the country.

Bandula Jayasekara has repeatedly tweeted against Macrae, branding him an “LTTE (Tamil Tiger) terrorist from London” and accusing him of making “blood money”.

Rajapaksa added: “I will make sure you don’t get a visa to come to Sri Lanka.”

Ambassador Jayasekara also contacted a freelance PR agent to ask him to “track that LTTE tiger terrorist propagandist Callum Macrae and find how much $$$$ he earned so far”.

Macrae said responded ‘This is a regime which stands accused of some of the worst war crimes and crimes against humanity this century - of course they don’t want to be subjected to any kind of scrutiny at all.”

The Nobel Prize nominated journalist intends to visit Sri Lanka to cover the Commonwealth Heads of Government Meeting, which will take place in Colombo from 15 to 17 November.

There had been calls for the British government to boycott the event and Alistair Burt, parliamentary under-secretary of state at the Foreign and Commonwealth Office has previously said: “We will make it clear to the Sri Lanka Government that we expect them to guarantee full and unrestricted access for international press covering CHOGM.”

Responding to Jayasekara tweets, Siobhain McDonagh, MP for Mitcham and Morden and vice-chair of the All Party Parliamentary Group for Tamils, said: ‘The tweets threatening to deny Callum Macrae entry to Sri Lanka to report on the Commonwealth conference tell us all we need to know about that country’s respect for press freedom.

“It also throws into sharp relief the moral ambivalence displayed by the UK government in declaring it will attend. Alistair Burt’s insistence that the Sri Lankan government guarantee free and unrestricted access for the media is simply incompatible with these remarkable threats from a Sri Lankan diplomat.”

Macrae is currently touring his film No Fire Zone: The Killing Fields of Sri Lanka across Australia, New Zealand, Malaysia and Canada.