Apple has suffered another blow in its global patent battle with Qualcomm as it was forced to pull older iPhones from its shelves in Germany. Currently the German Apple store offers the iPhone XS and XR but not the iPhone 7 or iPhone 8.

Qualcomm says Apple was forced to pull its older smartphones due to a December 20 patent ruling in Qualcomm's favor.

"The Court found that Apple is infringing Qualcomm’s patented power savings technology used in smartphones," Qualcomm wrote. Qualcomm needed to post a €1.34 billion ($1.53 billion) bond with German courts for the ruling to take effect, which it has now done.

In addition to pulling iPhones from its own physical and virtual shelves in Germany, Apple must also recall iPhones from third-party retailers in Germany, Qualcomm says.

In the past, Apple often used Qualcomm chips in iPhone models. But recently the companies haven't been getting along. Early last year, Apple sued Qualcomm in the United States and in China, accusing the company of extortion and anticompetitive conduct in its negotiations over patent licensing.

Qualcomm fought back. In November, Qualcomm won a patent ruling in China that Qualcomm said barred Apple from selling iPhones nationwide—though Apple claimed a software update would work around Qualcomm's patents.

As relations with Qualcomm cooled, Apple began working with other chipmakers instead, including Intel. In September, Qualcomm sued Apple, claiming that Apple shared proprietary details with Intel about Qualcomm's modem chips.

Meanwhile, Qualcomm is facing off in court Friday against the US Federal Trade Commission, which has accused Qualcomm of abusive licensing of mobile chip patents. If the US government prevails in the case, that would strengthen Apple's hands in negotiations with Qualcomm.