Federal parliament resumes on Tuesday for the first time since just before Easter with the focus on the budget and economy.
However, the High Court could throw the political debate off kilter with a judgment due on Wednesday into the eligibility of Labor senator Katy Gallagher.
Senator Gallagher is set to find out whether the court accepts her argument she took all possible steps to renounce her British citizenship before nominating for the 2016 election.
Prime Minister Malcolm Turnbull and Treasurer Scott Morrison will be aiming to keep the focus on the government's economic message.
The Senate will kick off the week debating laws to set up the Skilling Australians Fund, to provide $1.5 billion to the states and territories for apprenticeships and traineeships.
The fund will be financed by a levy on employers who sponsor foreign workers.
The Senate is also set to debate a motion to disallow changes to the Murray Darling Basin plan, which is set to fail after Labor reached an agreement with the government.
Mr Morrison will deliver his budget speech on Tuesday night, before doing a media blitz on Wednesday and Thursday to get his message across.
Labor leader Bill Shorten will give his reply on Thursday and is expected to be able to one-up the government due to Labor's planned budget changes, meaning he has more money to spend.
He told caucus on Monday night the government's 2014 budget was initially well received, until Labor pointed out the unfairness in it.
Mr Shorten said the coalition will be "arrogant and aggressive" about the budget, but it's a fight Labor can win.
In Question Time, the government is expected to focus on its strong jobs and economic record, while Labor will attack the need for corporate tax cuts.
In the lower house, MPs will debate legislation providing the Home Affairs Minister with new powers and make changes relating to the attorney-general's oversight of intelligence, security and law enforcement agencies.
