Prime Minister Scott Morrison says visa charges will be waived for international students and working holiday makers. 

In an attempt to encourage the vital economic class of students and working holidaymakers back to Australia, the PM says any who arrive in Australia will have their visa application fees rebated.

Mr Morrison announced the changes in response to large workforce shortages caused by the spread of the COVID-19 Omicron variant.

“What we'll be doing is we will be rebating the visa application fees from all those who arrive today,” he said. 

International students will have fees waived for eight weeks, and 12 weeks for working holidaymakers.

“My message to them is come on down,” he said.

“We want you to come to Australia and enjoy a holiday here in Australia - move all the way around the country and, at the same time, join our workforce.”

It should save students and holidayers several hundred dollars.

"We are putting out the welcome mat," Treasurer Josh Frydenberg told reporters.

The federal government has also scrapped a 40-hour per fortnight working cap for foreign students in sectors affected by workforce shortages.

Official stats suggest there are about 325,000 foreign students in Australia - with an estimated 150,000 still offshore, and there are an estimated 18,500 onshore working holiday makers onshore and 23,500 offshore.

Mr Morrison has also announced $3 million would go to Tourism Australia to support a marketing program targeting backpackers and students.