Prime Minister Tony Abbott has put the abolition of the carbon and mining taxes back on Parliament's agenda this week as he prepares for new senators to take up their seats next month.
But Mr Abbott has given the Government just four days to pass billions of dollars of savings and cuts to welfare payments in order to meet a July 1 starting date.
This week is the final sitting week for the current Senate, where Labor and the Greens can combine to block Government legislation.
From July 7 - when the new Senate will sit for the first time - Mr Abbott will have to cobble together the support of six of eight right-leaning crossbenchers to pass Bills to overcome Labor and the Greens' objections.
Mr Abbott said yesterday the carbon tax repeal Bills - already rejected by the Senate once - would be reintroduced in the House of Representatives today.
"Scrapping the carbon tax is a vital part of this Government's economic action strategy because the carbon tax is bad for jobs, it hurts families and it doesn't help the environment," he said.
The mining tax repeal Bills would also be reintroduced this week.
The Climate Institute yesterday enlisted former Liberal leader John Hewson and a pair of dinosaur puppets on the lawns of Parliament House to launch a campaign urging senators to reject the repeal of the carbon tax.
Taking aim at the "dinosaurs" of politics and business, Dr Hewson accused Mr Abbott, his former staff member, of waging a scare campaign against addressing climate change properly.
"We can't afford as a nation to get this wrong," he said.
The Government is expected to get the necessary votes from the new right-leaning crossbench to scrap the carbon and mining taxes but a raft of Budget measures face an uncertain fate.
Proposals to save about $5.7 billion in welfare spending were only introduced into Parliament on Thursday despite many meant to start from tomorrow week.
Labor has promised to oppose many of the measures.
Opposition Leader Bill Shorten accused Mr Abbott of hiding from scrutiny by deliberately bundling a host of Budget measures together at the same time it was trying again to repeal the carbon and mining taxes.
We can't afford as a nation to get this wrong."
- John Hewson * Former Liberal leader