Watch Marina Jenkins' report
A veteran from Plymouth who runs an animal sanctuary in Kabul has vowed to get his staff to safety or "die trying".
Pen Farthing had hoped to get 71 people and more than 100 animals safely to the UK after raising $500,000 to charter a jet.
But doubt has now been cast over his plans amid an apparent hold-up with the appropriate clearance from the Ministry of Defence.
As a British citizen, Pen is able to leave Afghanistan but has said he will not desert his staff and animals.
The former Royal Marine received assurances from Prime Minister Boris Johnson that a plane would be sent to support him.
Pen had even found a way to get his staff safely to Kabul Airport, which has descended into chaos as people attempt to flee the Taliban.
But now Pen is concerned his staff and animals are trapped, claiming discussions with the MoD - which needs to give clearance for the flight to take off and land in Afghanistan - have broken down.
Pen founded the Nowzad animal shelter in Kabul rescuing dogs, cats and donkeys after serving with the British Army in Afghanistan in the mid-2000s.
Appearing on Good Morning Britain on the morning of Monday 23 August, Pen spoke of his relief when it emerged the UK Government had granted visas for all of his staff and their families.
"There is a lot going on, Boris Johnson has granted permission my team to come to the United Kingdom which is fantastic," he said.
"I don't care what political party you are get behind him. He is behind our mission to get our staff and animals out of Afghanistan."
He was unable to divulge how he would be getting his team to Kabul Airport Pen but he simply said 'Taliban Taxi'.
That meant 71 people would be able to come on the plane and plans were also put in place for the animals to be brought safely out of the country.
But just hours later he told ITV West Country those plans may not come to fruition.
"We don't have a plane in the coming days, right now there is a rift between Boris Johnson and the Ministry of Defence," Pen claimed.
"My direct line to the MoD has been cut off, they have left me, one of their own out here on their own."
He says he will now have to try and get his team out of the country on his own.
"I have no back up and now only have one option," he said.
"I have to try and get my team in to Kabul Airport and the animals as well. There is a good chance we are not all going to get in."
Pen Farthing talks about ongoing problems for him and his staff
"We were really positive and happy and thought we had a chance. I have no chance now, all we can do is try and make our own way to the airport," he said.
"You have seen what is going on there the last few days and it is not good.
"Somebody at the MoD needs to help us out. I don't understand it - they are playing with people's lives.
"I served my country for 22 years and right now they have turned their backs on us", he said.
"I am going to go for it, we are going to try and get our teams in to that airfield. Whatever it costs."
There are 98 dogs and 79 cats at Pen's Nowzad sanctuary. Pen says they will be left to die on the airfield unless he can find a solution within the next few days.
"We are running out of time, we have seen today the Taliban is not going to extend the flight corridor deadline past the end of August," he continued.
"I need to be getting down to that airfield now. I am not going to take any resources, we have our own supplies. If we can not get that flight then these animals are going to die on that airfield.
The Ministry of Defence has been contacted for comment.