In the early hours of Monday morning, more than 200 relatives of Argentinian soldiers killed in the Falklands war are to take a three-hour flight to RAF Mount Pleasant, the remote islands’ main airport. They will then travel by coach to an isolated, often windswept cemetery where, for the first time, they will know they are standing by the grave of their loved ones.

For many Argentinian families that have been able to visit the islands occasionally since the war in 1982, there has been no specific grave by which to mourn and grieve, only a graveyard.

The bodies of 121 soldiers were never identified and the stark inscription on each gravestone reads only “Argentinian soldier known only to God”.

In desperation, some mothers kissed every grave, knowing one kiss at least was being given to their son.

Now, through an extraordinary blend of sensitive humanitarian cooperation, individual perseverance over sometimes government indifference and advances in DNA, the bodies of 90 soldiers have been identified.

In a simple, deeply emotional ceremony, including a Catholic mass delivered jointly by Enrique Eguía Seguí, the auxiliary bishop of Buenos Aires, as well as Anglican and Catholic priests from the islands, the families will be reunited with their lost sons. Inscriptions with names will have been placed on the graves. The soldiers will no longer only be known solely to God, but once again to their families.

The reunification after 36 years became possible when last June a team of scientists working with the International Red Cross, including both Argentinian and British forensic experts, spent a fortnight on the islands taking DNA samples. The samples were then matched against those of their relatives.

One of the relatives, Maria Fernanda Araujo, told the Guardian: “It will be a difficult day, with so much strong emotion, but it is necessary. Many of the families come from isolated and quite humble parts of Argentina. Some are very old and in wheelchairs. It is going to be very difficult for some – it will be the first time they will be in front of the grave of their child. It will be hard to get them to leave.”

At the age of nine she lost her brother Elbio Eduardo Araujo, killed on 11 June 1982 in the final days of the war at Mount Longdon, a bitter and decisive battle. She still carries pictures of the two of them together.

Now chair of the Malvinas Fallen Relatives Commission, Araujo stresses she hopes the day has a wider meaning. “In that moment, and in that sacred place, we will give a symbolic embrace of our families and our beloved to put aside the differences we had in previous years. In the name of the families, again as a symbol, we will give a wreath of flowers to be taken to the British soldiers in their cemetery in San Carlos. The hope is that we can get over this pain by releasing love and trying to stop conflict, either internal or external.”

Falklands: Argentinian soldiers' relatives to put names on graves Read more

The planning for the day has been meticulous. There will be no flags at the mass, either British or Argentinian, but a guard of honour with Scottish pipes will sound in homage.

The relatives, on two planes flying half an hour apart, will be accompanied by doctors, psychologists and Claudio Avruj, a member of the Argentinian human rights committee. They will land close to 9am and depart in the afternoon, spending no more than 10 hours on the islands. Contingency plans have been laid if the notorious Falklands weather makes it impossible for the planes to leave.

Araujo said it was not straightforward to persuade all the families to cooperate with the voluntary identification by giving finger samples of blood. Similarly, many in government until recent years were indifferent, regarding the dead soldiers as victims, not heroes. The state’s focus was instead on the disappeared of the dictatorship.

She said: “Those that opposed the identification process filled our heads with phantoms – that in the cemetery you would find nothing, and if they found anything the bodies would be taken back to the continent.

“My mother felt there was no need to open the tombs because she said she knew he had died in the Malvinas [the Argentinian name for the Falklands]. But she came to understand that other families wanted to identify their children’s grave.”

She added: “The more we can travel to the island, the better the relationship has become. They have always been very respectful, and us to them.”