They say the federal government must relax its limit on overseas students being allowed to work – legally – for no more than 20 hours a week.

Leaders from the Australian National University, University of Canberra and Canberra Institute of Technology came together to tell Fairfax Media they can not study if they are hungry.

They say when they look for extra work, they are at the mercy of unscrupulous employers who pay cash-in-hand at below award rates.

The students fear that if they complain about being ripped off by employers, they will be deported for breaching their visa conditions.

Drivers at the Gungahlin Crust Pizza store, including international students, won backpay this month after complaints about their working conditions were aired by Fairfax Media.

Nnaemeka Nwosu, who is studying a masters of international development at UC, said there should be flexibility with the limit on working hours.

"One size can't fit all," he said.

"There are students from Africa, south-east Asia and South America who are particularly finding this Australian environment quite expensive.

"I understand the rationale behind the limit being created in the first place, the 20-hour week, to give students enough time to try to study.

"But if a student is hungry or can't get money for rent, that student will still not be able to study."

Immanuel Ravi from Indonesia, who is studying media production at UC, said most international students did not know their rights.

"So it's really easy for employers to exploit them," he said.

"Sometimes we just have to take extra work for us to provide for ourselves.

"Finding jobs is not easy so sometimes you just have to take it whether it's a good offer or not, we have to accept it."

Chris Wilson, a domestic student and president of the ANU Postgraduate and Research Students' Association, also said the 20-hour limit was leading to exploitation.

"I've heard of many situations of students being exploited, whether that's being told to accept a lower wage, to be able to look the other way on the hours, in order to get enough money to be able to afford food and accommodation in Australia which is a very high cost country," he said.

"We're trying to address that through the removal of the 20-hour work week or to reposition that in a situation across the whole sector that encourages students to be able to survive while they're here, to thrive and to be able to get the high quality education that Australia is known for."

Lekh Raj Pokhrel from Nepal, said being allowed to work only 20 hours a week to support himself was very hard,

"It's a struggle when you're in Australia," he said.

His parents used to send him money, before a massive earthquake hit his home country.

"Now I have to send them money, they are surviving in tents, that's a big problem for Nepalese students in Australia," he said.

Nawaf Ibrahim from the Maldives, is studying public administration at UC on a scholarship but says many other students face a battle,

"The 20 working hours doesn't help at all, it leads to people working for cash in hand," he said.

"I've heard of cases of students working for accommodation, for example, instead of pay, or getting food instead of pay so it just leads to further problems, not being able to sustain themselves."

Kofi Osei Bonsu who is studying media at CIT Bruce, said the federal government should change the work limit.

"The 20 hours per week is not enough, seriously," he said.

"There are a lot of companies that are really taking advantage of international students, it's widespread.

"I need to be very frank with you, some students are already doing 40-plus hours work a week because they cannot survive."