CANBERRA, Australia (AP) — Australia's opposition party officially launched its election campaign on Sunday, putting health care and climate change at the forefront of its bid for election within two weeks.

Center-left Labor Party leader Bill Shorten promised to spend billions of dollars providing free dental care for pensioners, reducing waiting times at hospital emergency departments and eliminating costs for cancer patients.

"Cancer makes you sick. But in a rich country like ours, it shouldn't make you poor," Shorten told supporters at a convention center in Brisbane city.

Shorten also highlighted Labor's pledge to reduce Australia's greenhouse gas emissions by 45% below 2005 levels by 2030. The conservative coalition government has committed to reduce emissions by 26% to 28% in the same time frame and warns that Labor's more ambitious target would wreck the economy.

Shorten said half the Liberal Party-led coalition "simply don't believe climate change is real and the other half just don't care."

Curbing greenhouse gases is a divisive issue in a country that is the world's biggest exporter of coal and liquefied natural gas. Former Prime Minister Malcolm Turnbull was overthrown by hard right wingers in his own party in August in part because of his energy policy that would have increased electricity prices to reduce emissions.

Turnbull was replaced as prime minister by Scott Morrison, who has attacked Shorten's lack of detail on how much Labor's emissions reduction target would cost the economy. Shorten argues that failure to act on climate change also carries an economic cost.

"He doesn't know the price of anything because he's not the one who is going to have to pay for it," Morrison told a Liberal Party rally on Sunday. "You're the ones who are going to have to pay for it right across Australia."

Morrison said his government would reduce taxes for all if it is elected on May 18 for a third three-year term.

Most opinion polls since the 2016 election have put Labor ahead of the government.

Labor's emphasis on health plays on one of its strengths. A Labor government in 1984 introduced Australia's popular publicly funded universal health care system known as Medicare.

The government accuses Labor of lying to voters in text messages days before the 2016 election that the conservatives planned to dismantle Medicare. The government blamed Labor's so-called "Medi-scare campaign" for the loss of 14 seats at the 2016 election, leaving the ruling coalition with a single-seat majority in the House of Representatives of 76.

The government now has only 74 seats after Turnbull quit Parliament and one of his supporters became an independent lawmaker. Labor holds 69 seats. The size of the House of Representatives, where parties need a majority to form a government, will expand from 150 to 151 seats at the election.

Political parties officially launch their campaigns close to the election date when voters are starting to focus on competing policies. Morrison will launch the Liberal Party campaign next Sunday.

Labor's launch was held in Queensland state where Australia's oldest political party was formed by striking sheep shearers under a tree in the town of Barcaldine in 1891. Queensland is also a state where five electorates were won in 2016 by margins of less the 1% of the votes, including a Labor seat won by 37 votes.

Three former Labor prime ministers, Paul Keating, Kevin Rudd and Julia Gillard — the nation's only woman prime minister — were on hand to cheer Shorten on Sunday.

Keating led his government to one of the worst defeats in the 118-year history of the Australian federation in 1996. Shorten as a party powerbroker played a key role in Labor dumping Prime Minister Rudd in 2010 and Gillard in 2013, only to be return Rudd to the helm.

The only other surviving Labor prime minister, Bob Hawke, sent his apologies. The 89-year-old is Australia's longest serving Labor prime minister who introduced Medicare.