SYDNEY, Australia — Opposition politicians and environmentalists in Australia reacted with dismay Thursday to the country’s repeal of laws requiring large companies to pay for carbon emissions, saying that it made Australia the first country to reverse progress on fighting climate change.

The Senate voted 39 to 32 on Thursday to repeal the so-called carbon tax after Prime Minister Tony Abbott’s conservative government secured the support of a number of independent senators. The House of Representatives had voted earlier in the week to repeal the unpopular measure, which has been a highly contentious issue in Australian politics for seven years.

The tax was devised to penalize hundreds of Australia’s biggest producers of carbon emissions, setting a price of 23 Australian dollars, or $21.50, per metric ton of carbon dioxide when it was put into effect in 2012 under then-Prime Minister Julia Gillard of the Labor Party, which is now in the opposition. The price rose to 25 Australian dollars this month.

Mr. Abbott, of the conservative Liberal Party, who took office in September, made repealing the tax a central pledge of his election campaign, arguing that ending it would reduce electricity prices and enhance economic growth. But he struggled twice to get the measure through the Senate before the vote Thursday. The government now plans to introduce a range of measures that it says will encourage business to reduce pollution, rather than penalizing polluters.