Caught between a Sino-US trade war, political concerns over Chinese telecoms firm Huawei and slowing consumer demand, chipmakers in Singapore have started slowing production and laying off hundreds of jobs.

Progress toward a US-China trade deal has stalled while the Trump administration determines how to address Beijing's demands that it ease restrictions on Huawei Technologies, people familiar with the talks said.

The Chinese telecoms group is determined to accelerate efforts to become self-reliant.

President Donald Trump's decision to allow US companies to continue selling to Huawei followed an extensive lobbying campaign by the US semiconductor industry that argued the ban could hurt America's economic and national security.

Apple is manufacturing its new Mac Pro computer in China, according to people familiar with its plans, shifting abroad production of what had been its only major device assembled in the US as trade tensions escalate between the Trump administration and Beijing.

Trump said Saturday that "US companies can sell their equipment to Huawei," as long as the transactions won't present a "great, national emergency problem."

ARM instructed employees to halt "all active contracts, support entitlements, and any pending engagements" with Huawei and its subsidiaries to comply with a recent US trade clampdown.

A top business lobby group representing American firms in China said they have "real concerns" over how Beijing may respond to US action taken against Huawei. Speaking to the BBC, AmCham China chairman Tim Stratford said its members were worried about Beijing's response.