CANBERRA, April 14 (Xinhua) -- Australia's opposition leader has delivered his first major speech in the lead-up to May's general election, reaffirming his commitment to slashing the cost of cancer treatment.

Addressing a campaign event in Sydney on Sunday, Bill Shorten, the leader of the Australian Labor Party promised his supporters that he will not let them down if elected on May 18.

"I cannot promise these people that victory is assured. That will be up to the judgment of our fellow Australians," Shorten said, according to The Australian.

"But I can most certainly promise that my team and I will work as hard as we can, every day between now and the election," Shorten said.

"I can promise that at 6:00 p.m. (local time) on election night we will have given it everything we have," Shorten said.

"And if we do that, if everyone in this room, every one in our movement who is interested in the progress of this nation, if we all give it everything, that we have in the next 34 days, then we will make Australia a better country," Shorten added.

Shorten has previously promised to invest 2.3 billion Australian dollars (1.6 billion U.S. dollars) in Medicare, Australia's publicly-funded universal health care system, if elected to subsidize cancer treatments.

"My view is simple and Labor's promise is straightforward, if you are in the fight of your life, it should not matter whether you live in the city or the bush, it should not matter you postcode or your personal wealth, under Labor there is only one thing that matters, only one thing that you will need - your Medicare card," he said.