The Home Office has rejected a visa application from a family trapped in Afghanistan, whose son was evacuated to the UK during the fall of Kabul.

Ahmad (not his real name) was brought to the UK at the age of 10 with his uncle and aunt during Operation Pitting in 2021, when about 15,000 British nationals and eligible Afghans were evacuated from Afghanistan during a Taliban offensive.

Ahmad’s family, who are in hiding in Afghanistan, submitted family reunion visa applications to be reunited with their son in the UK in February 2023. The Home Office refused the application in June this year, saying this was not in breach of their right to a family life and that Ahmad, now 13, was not a valid sponsor as he had arrived in the UK through the Afghan citizens resettlement scheme (ACRS).

In a letter to Ahmad’s father, seen by the Guardian, the Home Office stated: “You have failed to show any exceptional dependency between you and your sponsor [Ahmad] … As such I am satisfied that this refusal has not breached your right to a family life.”

The Home Office also said Ahmad’s family were deemed not to be at “exceptional” risk in Afghanistan, despite the fact Ahmad’s father had told it he had worked for a company linked with the western effort in Afghanistan.

The letter said it had placed “little weight” on the claim that the family were “severely restricted by the Taliban regime” as they had been able to obtain identity documents since the Taliban took charge.

Ahmad’s father, who spoke to the Guardian through an interpreter and did not want to be identified, said: “My life is in danger because I worked with foreign forces … The decision from the Home Office made us very upset. We felt that we had the right this country would allow us to reunite with our child.

“It’s been for the past three years that we are missing one member of our family and his place is empty in our life, and that is our son.”

Since Ahmad arrived in the UK he has been living with his paternal uncle and aunt and has started school. His aunt described the teenager’s relationship with his family as “very close” and said she was shocked by the Home Office’s refusal.

“He is still a child,” she said. “We all know that children need their parents, especially when they are this age.”

Ahmad and his family are being represented by lawyers from the Afghan pro bono initiative, which is run by the refugee charity Safe Passage International and Refugee Legal Support. They have lodged an appeal against the Home Office rejection and are waiting for a hearing date.

According to his lawyer, Helena Cullen, Ahmad is one of about 80 children who were separated from their families in the chaotic circumstances surrounding the evacuation in 2021. Cullen hopes the government’s announcement in July of a new separated families visa route will offer Ahmad’s family and others fresh hope.

“This family was tragically separated during the chaos of Operation Pitting and have been fighting to reunite for the last three years, battling many hurdles just to get their family reunion application submitted,” Cullen said.

Dr Wanda Wyporska, the chief executive of Safe Passage International, echoed calls for the family’s reunion applications to be accepted.

“I know from speaking to our legal and safeguarding experts that this boy is depressed, his mental health is deteriorating and he is struggling at school, having not seen his family for three years. He has night terrors about the separation and worries about his family’s safety,” she said.

The Home Office said: “All applications are carefully considered on their individual merits and in line with the immigration rules.” The department said it was longstanding policy that it did not comment on individual cases.