WASHINGTON (REUTERS) - Walmart, Target and more than 600 other companies urged United States President Donald Trump in a letter on Thursday (June 13) to resolve the trade dispute with China, saying that tariffs hurt American businesses and consumers.

This letter is the latest of many sent to the Trump administration by Tariffs Hurt the Heartland, the national campaign against tariffs supported by more than 150 trade groups representing agriculture, manufacturing, retail and tech industries.

But it is significant as US-China trade tensions escalate and comes before a possible meeting between Mr Trump and Chinese President Xi Jinping at the June 28-29 Group of 20 summit in Osaka, Japan.

Mr Trump has said he wants to meet Mr Xi there and will decide on whether to extend tariffs to almost all Chinese imports after that.

With less than three weeks to go before talks between Chinese and US leaders, expectations for progress towards ending the trade war are low. Sources have told Reuters that there has been little preparation for a meeting even as the health of the world economy is at stake.

"We remain concerned about the escalation of tit-for-tat tariffs," the new letter sent on Thursday said. "Broadly applied tariffs are not an effective tool to change China's unfair trade practices. Tariffs are taxes paid directly by US companies... not China."

The White House did not immediately respond to a request for comment.

Walmart, the largest US private sector employer and the world's largest retailer, has said that tariffs will increase prices for US consumers.

"Trade overall has been good for Americans, good for consumers... and I realise it gets criticised at times," Walmart chief executive Doug McMillon said last week. He urged the Trump administration focus on how trade helps a broad number of people in the country and "not just those it harms".

Additional 25 per cent tariffs on US$300 billion (S$410 billion) worth of Chinese imports, on top of those already levied, would wipe out more than two million US jobs, the letter said, citing estimates from international consultancy the Trade Partnership.

They would also add more than US$2,000 in costs for the average American family of four and reduce the value of US gross domestic product by 1 per cent, it said.

"An escalated trade war is not in the country's best interest, and both sides will lose," the letter added.