BEIJING/WASHINGTON • China has lodged an additional complaint with the World Trade Organisation (WTO) regarding the US' proposed tariffs on US$200 billion (S$272 billion) worth of Chinese imports, the Ministry of Commerce said in a statement.

Monday's complaint followed one that the ministry filed on July 6 at the WTO about the US' early round of levies on US$34 billion worth of Chinese goods.

The tariff hikes targeting Chinese goods were based on Section 301 of the United States Trade Act of 1974, its domestic trade law.

"The US' unilateral initiation of a trade war has no international legal basis at all," the Chinese ministry said last week.

Meanwhile, the Trump administration is hitting back at what it considers unjustified retaliatory tariffs that were imposed in response to US steel and aluminium duties.

US Trade Representative Robert Lighthizer said it launched formal challenges at the WTO on Monday against China, the European Union, Canada, Mexico and Turkey for retaliating against steel and aluminium tariffs.

The Trump administration earlier this year imposed 10 per cent duties on aluminium and 25 per cent duties on steel after finding that imports of the metals pose a risk to national security.

"Instead of working with us to address a common problem, some of our trading partners have elected to respond with retaliatory tariffs designed to punish American workers, farmers and companies," Mr Lighthizer said in a statement.

He said the US would take "all necessary actions" to protect US interests and urged trading partners to "work constructively" with the Trump administration to address overcapacity in both metal sectors.

Canada, China, the EU, Mexico and Turkey have imposed retaliatory tariffs on US$23.4 billion worth of US goods in response to President Donald Trump's tariffs on steel and aluminium.

A European Commission spokesman said that while the bloc's decision to retaliate was proportionate and WTO-compatible, the US is entitled to seek an independent review in which the EU will explain and defend its position.

The Canadian government said its tit-for-tat tariffs are allowed under the rules of the WTO and North American Free Trade Agreement.

The Mexican government said in a statement that it will look at the US request with the goal of answering it in the next 10 days.

The US' national security rationale for its steel and aluminium tariffs was unjustified, according to the statement, and Mexico's response was a reaction to that. The Mexican government promised to continue to defend its national interest.

The Trump administration has criticised the WTO for encroaching on US legal sovereignty and failing to rein in China's alleged violation of global trading rules.

Mr Trump earlier this month threatened to take action against the WTO after news service Axios reported that his administration had drafted legislation to withdraw the US from the organisation, a move that he had repeatedly told advisers he was considering.

CHINA DAILY/ ASIA NEWS NETWORK, BLOOMBERG