"We will oppose the legislation in the senate, that is the right thing to do," Abbott told reporters, saying that he was "not frightened of an election on this issue".
Abbott's victory came after Malcolm Turnbull, the now ousted party leader, sparked a party revolt by supporting the government's emissions trading legislation, which is
strongly opposed by the industry and agriculture lobbies.
Following his victory, Abbott played down his earlier comments that climate-change science was "crap" as "a bit of hyperbole".
"I think man does make a contribution. There's an argument as to how great that contribution is - and, second, what should be done about it.
"The last thing we should be doing is rushing through a great big new tax just so Kevin Rudd can take a trophy to Copenhagen," he said.
The Copenhagen climate change summit, due to take place next week, is intended to arrive at a successor treaty to the Kyoto Protocol, which expires in 2012.
Failure to pass the cuts ahead of the UN summit would jeopardise Australia's ability to be fully active in the negotiations.
Rudd sought to place Australia, the developed world's worst per capita polluter, at the centre of the international debate despite its accounting for just 1.5 per cent of global emissions.
The bill's defeat would give Rudd the power to call Australia's first "double dissolution" election since 1987, although the prime minister has played down the prospect.
Rudd started a three-year term in February 2008.