A crackdown on tax advisor misconduct in the wake of the PwC scandal will be a step closer when the government brings proposed new laws to parliament.
Bigger fines for tax avoidance, allowing more time for legal action, modernising secrecy laws and whistleblower protections are among a suite of changes set to be introduced in the lower house on Thursday.
PwC came under fire earlier this year after shocking revelations some staff leaked confidential information they'd got from Treasury to drum up new business.
The proposed changes would increase the maximum penalty for advisors and firms running tax avoidance schemes from $7.8 million to $780 million, with surrounding laws expanded so the fines are easier to apply.
Regulators such as the Australian Taxation Office and the Tax Practitioners Board would also have more power, with the latter to have more time to complete complex investigations and to refer misconduct by advisors to professional associations.
Assistant Treasurer Stephen Jones said it was the "biggest government crackdown on tax advisor misconduct in Australian history".
"The PwC scandal exposed severe shortcomings in Australia's regulatory frameworks undermining community confidence in our tax systems," he said in a statement.
"(The) bill reflects the government's decisive next step in better regulating tax practitioners, and strengthening accountability within the tax system."
Separate legislation being introduced includes changes to the Petroleum Resource Rent Tax announced in May's budget.
The reforms are forecast to increase tax receipts by $2.4 billion over the next five years by limiting assessable income that can be offset by deductions to 90 per cent.
"The PRRT changes will ensure the offshore LNG industry pays more tax, sooner," Treasurer Jim Chalmers said in a statement.
"These reforms deliver Australians a fairer return from the nation's natural resources, provide certainty to industry and ensure Australia remains a reliable trade and investment partner."
The Greens have argued the changes should go further to reap more tax revenue.