By Matt Siegel
SYDNEY (Reuters) - Australia's parliament began an acrimonious final sitting day before a May budget on Thursday, with Prime Minister Malcolm Turnbull considering dissolving both houses of parliament and calling an early election to end a hostile Senate.
Independent and minor party senators elected at the last election in 2013 have stalled key aspects of the government's agenda, including changes that would make higher education and health care more expensive and limit access to welfare.
Senate voting reforms proposed by Turnbull, and being debated on Thursday, would make it harder for smaller parties to enter parliament through vote sharing deals, and are supported by the opposition Greens Party, which controls enough of the Senate to insure passage of the reforms.
Australian Motoring Enthusiasts Party Senator Ricky Muir was elected in 2013 with less than one percent of the popular vote as a result of complex vote sharing deals between small parties agreed to privately ahead of the vote.
Immigration Minister Peter Dutton predicted passage of the voting changes, which are supported by business groups angered by three years of partisan gridlock amid an economic slowdown driven by a plunge in commodities prices.
"We can’t go to the ballot box, cast a vote and not know where that vote is going to end up," Dutton said in an interview with Sydney's 2GB Radio.
Turnbull has consistently led opinion polls since he came to power last year and his ruling Liberal-National coalition is leading the opposition Labor party comfortably in recent polls. But there are signs Turnbull's honeymoon period as prime minister may be ending, prompting election speculation.
An election is due by January 2017, but has been expected to be called for the second half of 2016.
Turnbull is unlikely to opt for a rare double dissolution election, which sees both houses of parliament face voters, if the voting reforms fail to pass as it could return a similarly hostile group of smaller parties as he currently faces.
Under Australia's constitution, Turnbull faces a May 11 deadline to call a double dissolution election and the earliest it could be held is June.
In order to call such a poll he needs a piece of legislation twice defeated by the Senate as the trigger.
He has a labor bill which has been defeated once, but would need to recall parliament early to May 3 to allow time to reintroduce the labor bill and have it voted on by the Senate before the May 11 deadline.
But to recall parliament early Turnbull must bring forward the May 10 budget as an excuse.
(Reporting by Matt Siegel; Editing by Michael Perry)