Deputy Prime Minister Julia Gillard has made a last-ditch plea to the opposition to allow passage of Labor's student income support changes.
The federal government's Youth Allowance changes are due to go before the Senate again on Thursday, two days after the coalition moved to delay a vote on the legislation.
With the opposition and Family First senator Steve Fielding indicating it will block the legislation, Ms Gillard has pleaded with the opposition to reconsider.
"Its not too late for this legislation to go through," she told ABC Television on Thursday.
"If they don't, the consequences for students right around the nation next year are really catastrophic."
Ms Gillard says blocking the legislation would lead to 150,000 university students being denied scholarships while another 100,000 first-time Youth Allowance recipients would miss out on being paid.
The government wants to reform its student income support scheme to make it harder for university students to prove they are financially independent from their parents by working.
The only way they can do that under the government's changes will be to find 30 hours of work a week for 18 months.