BEIJING - US trade sanctions will hit the world economy, Beijing warned Wednesday, after President Donald Trump threatened to impose fresh tariffs on imports from China.

Trump said he was "considering all options," including tariffs and quotas, after he accused China of decimating the American steel and aluminium industries.

Washington has already imposed a range of tariffs on Chinese-made goods, sparking fears of a tit-for-tat trade war between the world's top two economies as China also threatens to take action.

Foreign ministry spokesman Geng Shuang told reporters that "any sign of unilateralism or protectionism will ... worsen global trade issues and will hurt the recovering momentum of the world economy".

He added that with the sheer volume of trade and integration between the US and Chinese economies, some friction was natural.

However, "China always regards the US as an important cooperation partner in trade and economy, and we hope we will continue to open our respective markets wider", Geng said.

The Trump administration has two months to decide whether to take action on Chinese aluminium, steel and intellectual property practices.

China produces around half of the world's steel but stands accused of "dumping" cheap steel on global markets to gain market share.

The two countries have already begun trading sanctions in what China's commerce ministry warned could become a "vicious circle".

On Monday Beijing announced it had taken aim at imports from the US of styrene, a key chemical in the manufacture of styrofoam.

Last week it launched an anti-dumping investigation into sorghum imports from the US, worth almost $1 billion last year.

The measures come a month after the Trump administration slapped new tariffs on Chinese-made solar panels and washing machines, the most recent in a series of trade cases that have rattled Beijing.