Dr Alkatiri has long denied accepting any bribes. He would not say whether he would reply to the Oceanic lawsuit. He had previously said he been unable to defend his reputation over the claim as he had not been named as a respondent.

Alkatiri was served on his way to address the SEAAOC conference being held in Darwin this week. Alkatiri said ‘thank you very much’ after being handed Oceanic’s letter by a private detective and made no further comment, an Oceanic official told media. Mr Alkatiri had previously told Australia’s SBS television that he would have preferred to have been named as a respondent in the case so that he could defend himself.

Oceanic lawyer Dale Oliver said: "We will take you up on your challenge. We accept your offer to be named as a defendant." Oceanic lost a legal claim brought to bear in a Canberra court last year which alleged the Australian Government of breach of contract over its Timor Sea claim.

Oceanic has accused ConocoPhillips of bribing Dr Alkatiri with US$2.5 million in exchange for the rights to explore oil and gas in the Timor Sea. Oceanic claims it had previously been awarded the rights to the area when Timor Leste was part of Indonesia.

The Oceanic lawsuit claimed ConocoPhillips, Australia and Indonesia had conspired to steal an exploration permit granted by the previous ruler, Portugal, before Indonesia invaded Timor Leste in 1975.

The action against ConocoPhillips has severe implications under US anti-racketeering laws. It seeks US$10.5 billion in compensation, which could be tripled if the action is successful and found to be the result of a criminal conspiracy.