Cuts fuel fears among some Afghans that western governments are turning their backs on Kabul as Nato soldiers leave

The United States has stopped funding a charity that educates some of Afghanistan's most vulnerable abuse victims, including a tortured child bride and a teenager scarred by acid for refusing to marry a militia commander.

The decision to end financing for Aid Afghanistan for Education, which provides schools for girls and women excluded from government classrooms, came despite a pledge last month to spend more than $200m (£130m) on "women's empowerment" as foreign troops head home.

Since funds were cut off this spring teachers have been leading classes for free in the hope that the charity's director, Hassina Sherjan, can cobble together funds to pay their modest $140 monthly wages before they have to find new jobs.

It is not the only educational institution to lose US government funds as Washington's generous aid budget shrinks dramatically. It is down by about 50% from a 2010 peak, and the impact of the cuts is fuelling fears among some Afghans that as Nato soldiers leave their governments are turning their backs on Kabul.

The Afghanistan Technical Vocational Institute, which helps combat youth unemployment and a woeful lack of professional skills and training, is another organisation now "running on fumes", according to its founder and director Sardar Roshan, a former ambassador to Pakistan.

His teachers have worked for months without a salary and students chipped in to pay for their graduation this year, after funding ended in 2012. Roshan said promises of a new grant produced only limited cash for "capacity building". The US embassy denies promising more cash.

In 2010 Washington's development agency USAid spent $145m on Afghan education; this year it has requested less than $100m.

Part of the problem that has trapped the vocational school and the women's education charity is a commitment by all foreign donors to channel more aid money through the government. Their aim is to improve ministers' ability to handle funds, after years of watching the money pass through a virtual parallel administration run by foreign aid organisations.

USAid said both organisations were told in advance that their funding would be terminated or cut, and they could compete for $56m of funds in the community-based education project and $35m for technical and vocational education, all distributed by the education ministry.

The education ministry intended to fund the vocational institute, said a spokesman, Amanullah Aiman, pointing out that it was built on government land. Technical problems were delaying funds, and the institute's management was unhappy as there would be less money than USAid provided, he added.

He declined to comment on Aid Afghanistan for Education, saying he was not familiar with the organisation.

Aid Afghanistan for Education began life as an underground network of classrooms after the Taliban halted all female schooling, and grew to be a lifeline for women whose education was cut off by the Taliban's ban, by poverty or by early marriage.

An annual budget of about $1.5m is needed to pay for 13 schools in nine provinces, totalling more than 3,200 pupils. Some, in rural areas, are the only women's classrooms for miles.

"I am glad that this kind of school exists, because we will not be accepted in other ones," said Sahar Gul, a girl who was married at around 12 and then chained up and tortured by her in-laws for refusing to work as a prostitute. At the time of her rescue she was illiterate.

"I feel a lot of positive change, I am in fourth grade now," she added, sitting in the sun after morning classes beside classmate Mumtaz, a teenager burned by an acid attack after she refused to marry a militia commander.

Nine women from a shelter for abused women study at the school, alongside pupils such as 23-year-old Shaima, forced to drop out when she married and is now a mother of two. The headmistress has been honest with her students about the financial crisis they face.

"We are worried, because this is the only place we can study, we are married or too old for other schools," Shaima said. "Life is meaningless without education."

Sherjan said the lack of funding felt particularly bitter after the US embassy last month unveiled a $200m "Promote" project to support women's education and employment. She was told her organisation would not be eligible for a grant.

Overall the international community has promised about $4bn a year in aid for Afghanistan until 2016, and the two organisations need less than $5m a year to run large programmes with a strong track record tackling two fundamental challenges: education and youth employment.

But in a sea of promises, they simply cannot find the hard cash. "USAid says go to the [education] ministry, the ministry says they have no money, go to USAid," said Roshan with a grim smile.

Sherjan, an Afghan American, set up her schools to help girls excluded from the mainstream education system. She is in talks with officials to integrate their 13 schools, but it could take several years.

"We don't come under the ministry structure because they don't have a programme like this," Sherjan said from a study displaying a Harvard degree certificate and tributes to the work of an organisation, she left a comfortable life in the US to build up.

The US embassy said overage women were not barred from community schools, and other NGOs catered to them with "accelerated learning programmes", although two of three examples cited were for girls up to age 18, which would exclude most AAE pupils.

Sherjan said she would eventually like to wean the project off foreign aid, but the education ministry was not yet willing to absorb the schools and domestic philanthropy in Afghanistan had not kept pace with the dramatic increase in personal wealth.

"You really have to educate the private sector … that social entrepreneurship is maybe a better thing than buying another house in Dubai," she said.

At present, there is a campaign through the crowdfunding website Indiegogo to try to raise the bare minimum to keep the schools functioning.

For women's activists the funding shortfall is being interpreted as another warning sign that even if substantial western aid money keeps flowing, as attention shifts elsewhere, hard-won ground could be lost.

"There is no money for programmes such as AAE which have been there for years and are actually sustainable, but they have all these unrealistic programmes," said Wazhma Frogh, a prominent activist who is also a member of the charity's board.

"If you take the money away from a school which is the only hope for women in the area, how can you say you are committed to the women of Afghanistan."

Mokhtar Amiri contributed reporting