BEIJING, July 6 (Reuters) - Some major Chinese ports delayed clearing goods from the United States on Friday, four sources said, potentially disrupting imports worth billions of dollars as the world's top two economies head towards an outright trade war.
News of the hold-ups came as Washington imposed tariffs on $34 billion of Chinese imports from 0401 GMT on Friday.
Beijing had said it would retaliate with punitive measures on U.S. products worth a similar amount, including soybeans, pork and cotton, but it had not officially confirmed on Friday that they had taken effect.
The port of Shanghai had put on hold clearing some U.S. imports through customs, said an official at a company in the coastal city, which handles customs clearance for importers. He had spoken to customs officials.
There did not appear to be any direct guidance to hold up cargoes, but some customs departments were waiting until they had received official instructions from the central government on whether to start collecting the hefty new import tariffs on hundreds of products, the sources said.
A wine merchant in Shanghai, one of the country's busiest trading hubs, said customs brokers were also slowing the clearance process because of confusion about how and when to implement duties.
"They're holding everything ... because there's uncertainty," he said.
"But overall, this weekend they should be able to identify what the taxes are and how they should be implemented, and they should be processed as normal."