A national review of paid overseas internships is underway after a group of university students alleged they had been left stranded without working visas in Singapore.

Seven students from some of Australia's most prestigious universities say they paid up to $6,500 to the Hong Kong-based company Absolute Internship for its internship program and accommodation.

The students have told the ABC that when they arrived in Singapore to begin their internships, they discovered the company had not arranged for their mandatory work visas.

It is illegal to work in Singapore without an appropriate visa.

Caroline Mackay, 20, is studying commerce at the University of Western Australia and said she was deeply disappointed with her Absolute Internship experience.

She paid about $3,000 for a one-month internship in Singapore including weekend activities, accommodation, networking events and visas.

"Hardly any of those things were given to us," she said.

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On her fourth day of working as an intern, Ms Mackay was informed that she did not have a working visa.

"My company said to me: 'Sorry, Caroline you can't work with us anymore, Absolute Internship has not organised your working visa'," she said.

"I was left extremely distressed in a country I'd come over to work for a month."

Ms Mackay flew back to Australia without completing her internship. She asked for a refund but said Absolute Internship refused.

Gozoop, the marketing company that took on Ms Mackay, confirmed to the ABC it was forced to terminate the internship after four days because it was illegal to allow her to work without a visa.

Company refused request for refund

Freya Hirshman, 21, paid $4,000 for a one-month internship in Singapore with Absolute Internship.

The University of NSW design student spoke to the ABC from her three-star hotel room in Singapore, where she has been sharing a room with a stranger despite the company website promoting "exclusive housing".

Freya Hirshman was forced to share a room despite the company promoting exclusive housing. ( ABC News )

"It was just so uncomfortable to live here for a month with another person. It was really cramped," she said.

"It's just ridiculous considering we were shown all these pictures of this huge spacious room ... and also we'd get a kitchen, but we didn't.

"They said we'd get a pool, but we didn't."

Ms Hirshman asked Absolute Internship for a partial refund for services she paid for but did not recieve, but she said the company refused.

She pointed out that the work experience with a design company she received in Singapore was enjoyable and valuable.

Student threatened with legal action after making complaint

Seven Australian university students spoke to the ABC about their experience with Absolute Internship.

Several who did get to intern at Singaporean companies said they enjoyed the experience, however several did not get to that point.

One 19-year-old student, who wished to remain anonymous, said he lodged a formal complaint with the Singaporean police about Absolute Internship failing to organise his work visa.

The company then threatened legal action if he did not withdraw his complaint.

In an email, Absolute Internship wrote:

"Our legal advisers ... have advised us to take legal action against you. "We have also informed your university and made them aware of your damaging behaviour and the legal actions we are starting. "We are now expecting you to either change your attitude, cancel your complaint and agree to sign a dismissal warning document, or continue with your attitude and dismissal."

Another student who wished to remain anonymous was threatened with dismissal from the program after he complained about the service he paid for.

In an email to his mother, Absolute Internship wrote:

"Our legal representative has also been informed of [student's name] threats and blackmailing and actions will be taken very quickly should [his] attitude remain the same."

Universities review relationship with company

On its website, Absolute Internship states it frequently places students with well-known international companies, including PricewaterhouseCoopers (PWC).

But PWC told the ABC it did not have a relationship with Absolute Internship and had not had interns placed through the company.

Both Ms Hirshman and Ms Mackay said their respective universities promoted Absolute Internship on their websites and they believed that was an endorsement of the company.

The University of New South Wales, the University of Queensland and the University of Western Australia all told the ABC they were aware of concerns raised by their students in Singapore and were reviewing their relationships with Absolute Internship.

The University of New South Wales said it "has stopped advertising Absolute Internship's programs pending the outcomes of our investigations".

Two higher education organisations - the Australian Collaborative Education Network and the National Association of Graduate Careers Advisory Services - are conducting a national review into how universities deal with overseas internship companies.

Ms Mackay warned fellow students considering paying for an overseas internship to "definitely reconsider and definitely investigate further into the internship companies".

Despite repeated attempts to contact Absolute Internship, the company was not available for comment.