An investigation is needed into why thousands of Scottish university students have not yet received vital bursary and loans cash, the National Union of Students has said.

It has emerged that 7,572 students have not yet had their funding application processed by the Student Awards Agency for Scotland (SAAS).

The Scottish Government agency has received just over 151,000 applications for bursaries and loans, and has dealt with almost 144,000 of these. The remaining applications are expected to be processed by the end of November.

NUS Scotland president Robin Parker said the Government must now consider providing the organisation with extra resources so it can deal with the applications quicker. "Students who have not received support funding have every right to be upset, and are absolutely right to expect a better level of service," Mr Parker said.

"Many students rely on this funding to afford their education, and could struggle to remain at university without this much-needed support. If we want to retain students and prevent drop-out, we must give students the support they need and in a timely fashion.

"The Scottish Government needs to investigate why students will still be waiting for their support payments in November and look very closely at providing the additional resources SAAS would need to process applications quicker.

"In the meantime, students who are struggling should contact their university's student services department to see if they can qualify for hardship funding."

The SAAS website says its telephone lines are "extremely busy at the moment" and that students may be unable to get through. "For a number of weeks we have received higher than normal volumes of mail and emails. This has meant that we have not been able to reply within 30 working days. We apologise for this and are working hard to rectify it," it says.

"Our main priority at the moment is to process the remaining applications received after the guarantee date to ensure all students have received their initial financial support award for 2012-2013."

Tory education spokeswoman Liz Smith said the situation is "totally unacceptable" and demanded: "The Scottish Government must provide a full explanation of why there has been so much confusion and inefficiency within SAAS."