In this April 28, 2019, photo, workers assemble truck's tires at a plant in Nantong city in east China's Jiangsu province Sunday, April 28, 2019. China's exports fell in April amid a bruising tariff war with Washington, adding to pressure on Beijing on the eve of negotiations aimed at settling the fight over its technology ambitions. (Chinatopix via AP)

BEIJING (AP) — Ratcheting up tension ahead of talks in Washington, China vowed Thursday to defend its own interests and retaliate if President Donald Trump goes ahead with more tariff hikes in a dispute over trade and technology.

Beijing will impose "necessary countermeasures" if the increases take effect Friday as planned, the Commerce Ministry said. It gave no details but a ministry spokesman said Beijing has made "all necessary preparations," suggesting it might be bracing for worsening conflict.

Trump threw global financial markets into turmoil with Sunday's threat to raise import duties on $200 billion of Chinese goods from 10% to 25%. Trump complained Beijing was trying to backtrack on earlier agreements.

"If the U.S. tariff measures are carried out, China will have to take necessary countermeasures," said a Commerce Ministry statement. The spokesman, Gao Feng, said later that Beijing has the "determination and ability to defend its own interests."

The volley of threats reignited jitters about global economic growth, prompting another round of losses on world stock markets.

If tariff hikes go ahead, "risks of a financial market collapse, extreme risk aversion, and sharp slowdown in global growth will spike," said Philip Wee of DBS Group in a report.

In early trading, London's benchmark FTSE 100 index dropped 0.5% and France's CAC 40 lost 1.3%. Hong Kong's main benchmark skidded 2.4% and the Shanghai Composite Index lost 1.5%. Tokyo's Nikkei 225 lost 0.9%.

Before this week's acrimony, both sides said negotiations were making progress, which helped to stabilize financial markets. But economists warned a deal might be further away than investors hoped.

Trump raised duties on $250 billion of Chinese imports starting in July over complaints Beijing steals or pressures companies to hand over technology. That includes a 25% charge on $50 billion of goods and 10% on $200 billion.

Washington is pressing Beijing to roll back plans for government-led creation of Chinese global competitors in robotics, electric cars and other technologies. The United States, Europe, Japan and other trading partners say those violate Beijing's market-opening commitments.

American officials also want Beijing to reduce subsidies they say violate Chinese free-trade pledges and to narrow its multibillion-dollar trade surplus with the United States.

Beijing responded with penalties on $110 billion of American imports, but is running out of goods for tariff hikes due to their lopsided trade balance.

China's economy czar, Vice Premier Liu He, was leaving Thursday for Washington, according to Gao, the government spokesman.

Liu expressed hope the two sides will "meet each other halfway and care for each other's concerns," Gao said. However, he added, "at the same time, China has made all possible preparations."

Chinese authorities already have extended retaliation beyond imports by targeting operations of American companies in China. Regulators have slowed down customs clearance for their shipments and delayed issuing licenses in finance and other industries.

Beijing has an array of other weapons including launching tax, anti-monopoly or other investigations that can hamper company operations.

Chinese leaders see industry development directed by the Communist Party as a path to prosperity and global influence. They deny their plans violate Beijing's trade commitments but have offered to change details that provoke the most foreign opposition.

"China is not afraid of conflict," said the Global Times, a newspaper published by the ruling Communist Party's People's Daily that is known for its nationalist tone. It said Beijing has measures in place to "minimize losses" for its companies.

"Mentally and materially, China is much better prepared than its U.S. counterpart," the newspaper said.

Despite such bluster, factories in Chinese coastal regions that serve the U.S. market have been devastated. Industries including electronics that the Communist Party is promoting as China's economic future have suffered declines of up to 40% in sales to the United States.

That has increased pressure on President Xi Jinping, who political analysts say faces criticism within the ruling party that he has failed to manage Trump.

Chinese exports to the United States plunged 13% from a year ago in April and are off 9.7% since the start of 2019. Total Chinese exports sank 2.7% in April, well below forecasts of growth in low single digits.

Imports of American goods tumbled 26%.

FILE- In this July 5, 2018, file photo, a jockey truck passes a stack of 40-foot China Shipping containers at the Port of Savannah in Savannah, Ga. For months, the U.S. economy has shrugged off the tariffs slapped by America and China on tens of billions of dollars of each other’s goods. (AP Photo/Stephen B. Morton, File)
A woman smokes in a quiet shopping district in Beijing on Wednesday, May 8, 2019. China's exports fell in April amid a punishing tariff war with Washington, adding to pressure on Beijing on the eve of negotiations aimed at settling the fight over its technology ambitions. (AP Photo/Ng Han Guan)
Women walk pass advertisements in a shopping district in Beijing on Wednesday, May 8, 2019. China's exports fell in April amid a punishing tariff war with Washington, adding to pressure on Beijing on the eve of negotiations aimed at settling the fight over its technology ambitions. (AP Photo/Ng Han Guan)
FILE - In this Feb. 24, 2017, file photo, factory workers watch as a machine uses suction to lift a box containing an air conditioner at a Haier factory in Jiaozhou near Qingdao in eastern China's Shandong Province. For months, the U.S. economy has shrugged off the tariffs slapped by America and China on tens of billions of dollars of each other’s goods. The higher duties would cover thousands of Chinese imports, from refrigerators, air conditioners and washing machines to bamboo mats, microphones and cigarette paper. (AP Photo/Mark Schiefelbein, File)
FILE - In this Sept. 21, 2018, file photo, Mike Starkey offloads soybeans from his combine as he harvests his crops in Brownsburg, Ind. For months, the U.S. economy has shrugged off the tariffs slapped by America and China on tens of billions of dollars of each other’s goods. In drawing up its list of targets, Beijing focused specifically on soybeans and other farm products in a direct shot at Trump supporters in the U.S.  (AP Photo/Michael Conroy, File)