The parents of a seven-month-old baby who is stranded in Kabul without them say they are losing hope that they will be able to get her to the UK.
They say a five month delay in receiving their baby's British passport means their daughter is stuck in Afghanistan with grandparents.
The mother and British father say they had no choice but to return to the UK in May to retain the mother's UK visa.
The government said it would do all it could to help British nationals.
The baby's mother, an Afghan national, travelled to Afghanistan in September last year to see family.
She says she lost her UK ID card during her trip, and because of this, she was unable to return to the UK before her baby was born. Her partner joined her in December, and their daughter was born in Kabul in January.
The mother, who the BBC is not naming to protect her identity, was later issued a single-entry visa, which gave her 30 days to return to the UK to apply for a replacement permit.
The family say they had no choice but to leave their baby behind because of the limited window in which to travel back and renew the visa. They were also told the baby could not travel without a passport.
The mother speaks little English and needed the father to return to the UK with her to gain her replacement documents.
They hoped to return to Afghanistan as soon as the document was issued but events took over.
Although the parents received their baby's passport on Wednesday, there are now no commercial flights operating into and out of Kabul.
The baby remains in the care of her grandparents.
"I have been separated from my baby for months I am lost without her by my side and we are losing hope," says the baby's mother, who is in London.
"I beg the government to please help us bring my baby and family back to me."
The baby's father says they applied for the baby's passport in March.
"We miss her but we cannot do anything. We want to hug her, kiss her," he says.
"She is stuck in Afghanistan because of the passport delay. If the passport took less time, she would have been here with us."
British forces and embassy staff left Kabul before the baby could be brought to the UK.
"They said: 'Wait until she gets her passport.' I told them: 'It is going to be too late,'" the father says, referring to British officials.
"They said she's not British yet. You have to wait till her passport arrives, then she's British, then we can help you."
There are also concerns for the safety of the baby's grandparents because of the help they have given to UK and US forces since 2001.
The family has not left their house in Kabul for the past week for fear of reprisals from the Taliban.
"We helped the UK when they came to our country, we now need help," one family member said.
"We helped as much as we could but now we need help, nobody wants to know."
A Home Office statement said the UK will "continue to do all we can to deliver on our obligation to British nationals and eligible Afghans".
It said it did not comment on individual cases, but said "more must be done to support those at risk" and it will "urgently" look to establish a scheme to provide protection for Afghan citizens most at risk.
More than 16,000 people have been evacuated by the UK from Afghanistan, it added.
The Foreign Office said any British nationals who remain in Afghanistan and want to leave, and those caring for British nationals who are in Afghanistan, should continue to check travel advice and sign up for alerts.
"We will keep under constant review our means to help these people as the situation evolves," a statement said.
It said the UK has advised against travel to Afghanistan since at least 2001.
In April 2021 the UK advised British nationals there to consider leaving and on 6 August 2021 urged all those still there to leave immediately.