A lending service aimed at students has said it is "upset" at the accusation that it misleads customers, arguing student unions are "out to get us".

The National Union of Students (NUS) released a statement on Sunday saying student lenders Smart-Pig should "immediately stop" aiming its services at students.

"They style themselves as a friend of students but in reality they are anything but," NUS vice president Pete Mercer said.

"Some of their tweets are very misleading, even implying the NUS would be supportive of their loans when we have grave reservations about such credit."

The students' union is up in arms about the company charging 855% APR "despite presenting themselves as an 'ethical' leader" as well as incentivising students to borrow.

Lynne Condell, chair of the National Association of Student Money Advisers, also piped in, saying the company was "preying on students who really do not have a lot of credit options available to them".

But Tom Parks, director of Smart-Pig, told The Huffington Post "someone from the NUS is out to get us and I want to know who it is".

He said the company had been "very upset" by the accusations as the NUS had not attempted to get in contact before releasing the statement.

"They have been reluctant to talk to us," he continued.

He added there were a "number of" misrepresentations in the release and the union had "jumped the gun".

"The NUS's claims are contradictory. No payments have been made through our refer-a-friend scheme and new customers are not at any point offered a cash discount or introductory offer."

Smart-Pig was founded by Parks, only recently graduated from Warwickshire, and another individual who is still at university in Hertfordshire, in December.

"Current payday lenders do not service students adequately. If we weren't here they would be forced to go somewhere else. We have had considerable positive feedback."

Parks said there were policies in place to ensure students did not repay above a certain fraction. Although he would not disclose the percentage, he insisted it was an "ethical" amount.

But the NUS argues that students could be put at risk by the service:

"The idea that a payday loan should be the first port of call for a student struggling to make ends meet between loan payments is potentially very dangerous for students," Mercer continued.

He added students should talk to their union or financial advisers at their university about alternative options before considering taking out a loan.

Labour and Co-operative MP Stella Creasy said the incident was "another example of how these legal loan sharks cannot be trusted to act responsibly".

"I urge students not to be taken in by this company," the Walthamstow MP said.