US tariffs on a range of Chinese products are due to take effect from Thursday night.
Steep American tariffs on Chinese goods worth tens of billions of dollars are due to take effect when the clock strikes twelve on Thursday night, as US President Donald Trump fires the first salvo in a trade war between the world's top two economies.
China has vowed to respond "immediately", with experts warning that tit-for-tat measures between the two financial superpowers will send shockwaves around the global economy and strike at the heart of the world trading system.
The US will levy a 25-per cent tariff on more than 800 Chinese product categories worth around $34 billion and has warned of more to come if a trade war escalates.
Trump has threatened to progressively ratchet up US penalties to a total of $450 billion in goods - which would represent the lion's share of all of China's exports to the United States.
The tariffs target a broad spectrum of Chinese goods - such as passenger vehicles, radio transmitters, aircraft parts and computer hard drives - from industries Washington says have benefited from unfair trade practices.
A second tranche of 284 goods worth $16 billion is currently under review and could be added to the US list.
US 'firing at itself'
China is expected to retaliate as soon as the US tariffs go into effect, imposing duties on goods worth roughly the same amount but with a greater emphasis on politically sensitive farm agricultural products.
"The US has provoked this trade war. We do not want to fight it, but in order to safeguard the interests of the country and the people, we have no choice but to fight," said Gao Feng, spokesman for China's commerce ministry.
Christine Lagarde, head of the International Monetary Fund, has already sounded the alarm about a tit-for-tat cycle of retaliation, saying it would only create "losers on both sides."
And Gao noted that of the $34 billion in taxable products on the US list, about $20 billion - or nearly two-thirds -- are made by firms with foreign investment, including a "significant portion" from America.
"The US's measures are essentially attacking the global supply and value chain. Simply put, the US is opening fire on the whole world, and also firing at itself," Gao said.
'Better than ever'
Economists have for months warned of the potential damage to the US and global economies from aggressive trade policies and protectionism, which would raise prices and upend global supply chains.
But the Trump team has paid little heed to those warnings, with Commerce Secretary Wilbur Ross this week slamming them as "premature and probably quite inaccurate."
The US has provoked this trade war.
Trump himself tweeted this week that the economy is doing "perhaps better than ever" even "prior to fixing some of the worst and most unfair Trade Deals ever made by any country."
Under the banner of his "America First" policy, Trump has also targeted other traditional trade partners of the US, such as the European Union, Japan, Mexico and even Canada.
And signs are growing that the escalating global trade dispute is already affecting the world's top economy, with punitive duties now in place for steel and aluminium and the White House threatening to slap duties on auto imports.
Prices are rising, especially for steel and aluminium, and companies are starting to feel reticent about investments or planning to shift production overseas to avoid retaliation against US exports.
There have been immediate job losses at America's largest nail manufacturer, Mid-Continent Nail Corporation, due to rising steel prices amid warnings the company may have to shut down operations altogether.
Iconic American motorcycle brand Harley Davidson has announced plans to move production overseas to evade the retaliatory tariffs from the EU, drawing a barrage of attacks on Twitter from Trump.
The influential US Chamber of Commerce urged Trump this week to reconsider his actions, saying the counter-tariffs now affected $75 billion in American exports and endangered US jobs.
While Trump touts announcements of jobs created in steel plants due to the tariffs, manufacturing industries warn many more jobs will be lost in companies producing autos, auto parts, appliances and other goods that depend on imported components.
One study said as many as 400,000 jobs could be lost.