BEIJING (Reuters) - New European proposals to launch a “carbon border tax” will damage global efforts to tackle climate change, China said on Wednesday, urging a pushback against climate “protectionism”, a week before fresh global climate talks in Madrid.

In October, the EU’s new climate commissioner, Frans Timmermans, said research would begin on the new tax, aimed at protecting European firms from unfair competition by raising the cost of products from countries taking inadequate action against climate change.

But a border tax, together with a decision by U.S. President Donald Trump to withdraw from the 2015 Paris agreement, would seriously harm international efforts to tackle global warming, China said in a report on Wednesday, making its first formal comments on the proposals.

“We need to prevent unilateralism and protectionism from hurting global growth expectations and the will of countries to combat climate change together,” Zhao Yingmin, China’s vice environment minister, told a briefing.

Europe’s border tax, part of a proposed “green deal” aimed at making the block “climate-neutral” by 2050, is likely to face scrutiny in the latest round of annual climate negotiations set to begin in Madrid next week.

The idea has been welcomed by European steel association Eurofer but opposed by other industry groups concerned about retaliatory trade measures.

A tax would probably raise the price of Chinese goods in Europe, and Beijing believes it would violate a core principle of the Paris accord, which says richer countries should bear greater responsibility for cutting emissions.

In its national commitments to fight global warming, China - the world’s largest producer of greenhouse gas - has pledged to bring emissions to a peak by “around 2030”.

Although China has not set targets to cut absolute emission levels, it has cut its carbon intensity, or output per unit of economic growth, by 48.5% from 2005 to 2018, two years ahead of schedule, Zhao said.

The United States says the Paris accord is unfair to its firms as the pact does not do enough to tackle emissions from competitors in China and India.

China’s total annual emissions in 2018 were about 14 gigatonnes, the United Nations said this week, more than twice those of the U.S. Its emissions per person roughly match those of Japan and the European Union.

Beijing has promised “the highest possible ambition” when updating pledges next year, but has not yet offered to revise its 2030 target, although one expert says emissions could peak as early as 2022.

“The targets have been determined scientifically on the basis of economic development and current national conditions,” said Zhao, adding that achieving them calls for “extraordinary efforts”.

China’s efforts to build a nationwide carbon trading platform were also progressing, environment official Li Gao told the briefing, without giving a timeframe.

China has hit technical difficulties in meeting its pledge to launch the platform in 2017 among its Paris commitments.