Rizky Amelia – John Sauven, executive director of Greenpeace UK, was denied entry to Indonesia because he would "threaten the stability of the country," the immigration office has said.

"There was the possibility that [Sauven] would bring instability and disorder here," immigration spokesman Herawan Sukoaji said on Friday. When pressed for further details he declined to comment, saying that it was a "state secret."

He also declined to comment on whether, as has been suggested, the private sector had anything to do with the ban. The state, he said, had the right to prevent entry to any non-Indonesian.

Sauven was turned back by immigration officials at Jakarta's Soekarno-Hatta International Airport on Thursday afternoon. Sauven said in a written statement to the Jakarta Globe that in his more than 20 years working for Greenpeace, it was the first time he had been refused entry to a country.

"I had the correct visa, issued from the Indonesian Embassy in London, but apparently that doesn't count for very much when fighting against companies who have powerful connections in Government. At immigration I was informed I am on a "red list," banned from the country. No official explanation was provided," he said.

He said that during his visit, he had planned to meet with several government officials, the British ambassador, one of Indonesia's largest palm oil producers and visit an area deforested by a pulp and paper company in Sumatra.

Sauven denied that he had previously been refused entry to the country to attend a conference on deforestation where President Susilo Bambang Yudhoyono pledged to prioritize rainforest protection for the rest of his presidency.

Sauven said: "What sort of message does it send to the world about Indonesia when representatives from an environmental group working peacefully in support of the President's stated commitments to stop deforestation are banned from the country, whilst the companies undermining those commitments in Indonesia continue business as usual?"