According to a Nikkei story on Friday, Apple Inc has instructed suppliers to verify that shipments from Taiwan to China conform with the latter’s customs procedures to avoid them being held for inspection.

Trade tensions between China and the United States have risen following a visit to Taiwan by US House Speaker Nancy Pelosi and a legislative group.

According to the article, the iPhone maker informed suppliers that China has begun enforcing a long-standing rule that Taiwanese-manufactured parts and components must be labelled as created in “Taiwan, China” or “Chinese Taipei.”

Apple did not immediately respond to a request for comment.

In response to a media claim that shipments to Pegatron’s factory in China were being held for inspection by Chinese customs officials, Apple iPhone assembler Pegatron Corp said its mainland China plant is working properly.

Foxconn and Pegatron, two Taiwanese supply and assembly partners, are increasing manufacturing efforts as Apple prepares to debut the next iPhone in September.

(Adapted from Reuters.com)