An Afghan guard who helped provide security for the British embassy in Kabul has said he fears for his life after being rejected for the official relocation scheme to the UK because he was a contracted employee rather than a direct member of staff.

The man, whose name the Guardian is not printing to avoid exposing him to further risk, has been working for more than a year for GardaWorld, which provides security services to the British embassy. His role was to guard the accommodation where the British embassy bodyguards were housed.

After his car was set alight in a suspected assassination attempt, he applied for help from the British authorities under the Afghan relocations and assistance policy. His application was rejected in a letter from the Ministry of Defence last month.

His rejection letter read: “After reviewing your application, the Afghan threat and risk evaluation unit has determined that you are not eligible for relocation … We realise this will be disappointing news.” It said the man was not eligible “because you were not directly employed by Her Majesty’s government”.

He said he was puzzled about why he had been rejected, pointing out that his GardaWorld contract stated he had been “trained and recruited as a guard to British embassy Kabul project”.

He said he had not been given any guidance on how to appeal against the decision by members of the British embassy before it closed last week. Many of his colleagues had also been refused asylum.

“I gave up my whole life for this job. They do not give any advice and are not willing to talk about these issues, only to say we cannot help you in your transfer,” he said in a series of emailed responses to questions. “It did not matter to them whether we survived or not.”

GardaWorld provided all of the security for the British embassy in Kabul.

Oliver Westmacott, the president of GardaWorld’s Middle East operations, said he disagreed with the British government’s refusal of asylum to indirect staff members. He said the company was continuing to make the case to the Foreign Office that contract staff should also be given asylum.

“We feel a huge moral duty to do all we can to support our guards. Our responsibility is to do all we can to support his application to the British government for asylum because we absolutely recognise that there is a very real risk,” he said.

GardaWorld’s contracted employees were as vulnerable as embassy staff members, Westmacott said. “It’s the backbone, it is the fundamental security element to the British diplomatic mission in Kabul and they would not be there without having a contracted security provider,” he said.

The guard was recruited by GardaWorld, which had just taken over a number of British official security contracts previously held by G4S, last year and was employed at the gates of a housing block where about 18 ex-British military bodyguards were accommodated. The bodyguards provided security to senior members of the embassy staff.

One of those British bodyguards, also employed by GardaWorld, who was recently redeployed in Iraq, said he was very concerned about the man’s situation. Photographs show them outside the accommodation block building with other subcontracted members of security staff.

He said the Taliban would not be able to make a distinction between who was directly employed by the British embassy and who was a subcontractor. “He will be presented as someone who protected the British. We all worked together,” the British bodyguard said, adding that he felt “disgusted” with how the withdrawal had been handled.

“You establish a close relationship with the people you work with. He’s just had a baby boy, and he’s messaging me all the time asking what he can do; I feel helpless because I don’t know what to tell him. He’s 100% at risk.”

The Afghan man described feeling extremely vulnerable since the arrival of the Taliban in Kabul, and was concerned that he may again be targeted because of his decision to work for the British.

“I am feeling insecure and hopeless. I am waiting for death at any moment. The Taliban’s intelligence system is very strong and it has information about everyone,” he wrote. “I’ve never felt so scared in my whole life. The situation is very bad. The Taliban is everywhere, and security is not provided. Since yesterday, my fears have increased and I have left my home and taken refuge in my sister’s house.”

British forces from 16 Air Assault Brigade arrived in the Afghan capital this week to assist in evacuating British nationals and people eligible under the scheme.

A government spokesperson said: “Nobody’s life should be put at risk because they supported the UK government in Afghanistan. Over the last few weeks alone more than 1,700 Afghan staff and family members have been relocated to start their new lives in the UK. We have significantly expanded and accelerated the relocation scheme and carefully assess each applicant for eligibility and security.”

The man said he hoped his case would be reconsidered. “My only goal is to save my family, especially my son who has just been born.”

Westmacott said: “I fully appreciate he is in a desperate situation. We are continuing to advocate that we feel that these people are at risk and should be granted visas.”