As Timorese and Australians work round the clock preparing to celebrate two milestones in Timor-Leste’s recent history – the independence vote on 30 August and the arrival of peacekeeping troops on 20 September 1999, intimately connecting the two countries like an umbilical chord – two brave Australians are on trial for exposing a perfidy unworthy of a great country.

Xanana Gusmão is presiding over the organising committee of the two anniversary events. I peeked and walked in uninvited as our charismatic leader and chief negotiator gave instructions to some 100 officials involved in the festivity preparations.

Meanwhile in Australia, two men, former Asis spy Witness K and Canberra barrister Bernard Collaery are being tried … for treason? Disloyalty to country or to a government that was acting hors de loi? The two patriots were not passing on sensitive Australian security or economic secrets to Indonesia, China, North Korea or Russia.

Rather Witness K exposed the Australian government’s illegal spying operation against its ally, Timor-Leste, during bilateral negotiations. He and his lawyer, Collaery, now face jail time if convicted at trial.

The story is a simple, sad one, a story of chicanery, of innocence and trust betrayed. Sometime in 2004 as officials of our two countries were engaged in intense negotiations to resolve resource disputes in the Timor Sea, an Australian intelligence officer was ordered by his bosses in Canberra to plant listening devices in key Timor-Leste government offices to obtain sensitive information on its position and tactics.

Lawyer Bernard Collaery leaves the supreme court in Canberra on Tuesday. Photograph: Lukas Coch/AAP

In 2000, following the 1999 independence referendum, negotiations began in earnest over the fate of a significant oil field known as the Bayu-Undan, which like three other fields, would fall entirely within Timor-Leste’s exclusive economic zone (EEZ) if a medium line boundary were to be agreed between the two countries. These oil fields – Buffalo, Laminaria, Corallina, situated well within Timor-Leste’s EEZ – were being illegally exploited for several years, causing a loss for Timor-Leste estimated at several billion dollars. These oil fields are within the newly agreed permanent maritime boundary between the two countries.

Sadly, unknown to the Timorese leaders, the same government that in 1999 proudly helped save an impoverished people, had been busy plotting to deny us access to our oil and gas riches in the Timor Sea.

On the eve of independence in May 2002, assisted by senior UN negotiators, Timor-Leste prime minister Mari Alkatiri agreed with his Australian counterpart John Howard on a so-called resource-sharing agreement. Gas and oil were to be piped to Darwin some 500km away instead of to Timor-Leste, with Australia benefitting from most of the upstream activities. Timor-Leste would obtain 90% of tax and royalties. Left unresolved were Bufallo, Laminaria and Corallina fields.

In 2005 Australia and Timor-Leste reached yet another unfair, unjust agreement on an even greater gas field known as Greater Sunrise, that falls mostly in Timor-Leste’s EEZ if a median line were to be drawn between the two coastal neighbours facing each other. Without a medium line maritime boundary agreement, Timor-Leste would gain a meagre 18.09% of the major Greater Sunrise gas field.

Witness K, as the secret agent became known, and Collaery, are brave Australians, individuals with a conscience and courage, representing the very best of Australians as I know them – instinctively sympathetic to the underdog, the weak and vulnerable.

Peter Cosgrove, one of Australia’s finest soldiers, led a multinational force in 1999 to quell the violence and destruction brought on the people of Timor-Leste, setting our people free. But this gallantry was undermined by political elites and bureaucrats in Canberra who long before 1999 were determined to deny our impoverished people access and use of what they knew to be our riches in the Timor Sea, which are a fraction of all the oil and gas, coal and uranium in Australia’s own waters and land.

Now they are intent on punishing two Australians who are as brave as Cosgrove and the thousands of Australian men and women in uniform who were sent to our shores in 1999.

Knowing Australia as I do, I can sense the uneasiness and embarrassment felt across the political and legal minds in Canberra who hold the key to a decision on whether to sentence these two men to prison or to set them free.

These important people in Canberra can make only one honourable decision – dismiss the case, set Witness K and Bernard Collaery free. These men haven’t done any harm to their country. They honoured Australia. I urge our president Francisco Guterres to honour both men with Timor-Leste’s highest national award, the Order of Timor-Leste.

The 20 September celebrations will be somber and will have a bitter taste if Witness K and Bernard Collaery are not free.