A U.S. judge asked that the chief executives of Apple Inc and Samsung Electronics Co Ltd speak to each other at least once on the phone before a jury begins deliberating next week in the high-stakes patent trial between the two tech companies.

"It's time for peace," U.S. District Judge Lucy Koh said on Wednesday in a San Jose, California, federal court, just miles from Apple's headquarters.

Apple and Samsung are going toe-to-toe in a patents dispute mirroring a struggle for industry supremacy between the rivals that control more than half of worldwide smartphone sales.

Apple accuses Samsung of copying the design and some features of its iPad and iPhone, and is asking for a sales ban in addition to monetary damages. South Korea's Samsung, which is trying to expand in the United States, says Apple infringed several patents, including some for its key wireless technology.

The U.S. trial is now in its third week. Before the jury was brought into the courtroom on Wednesday, Koh told attorneys for the companies that they had succeeded in raising awareness about the importance of their intellectual property rights.

Top executives from both companies had participated in mediation with a U.S. magistrate judge several times. They remained far apart shortly before trial on how they viewed the value of each other's patents.

Koh asked them to explore settlement once again.

"I see risks here for both sides," Koh said.

Attorneys for both companies told Koh they would pass along the message.

Samsung continued presenting witnesses on Wednesday, including an industrial designer from South Korea who described developing the Galaxy line of tablets.

Speaking through a Korean interpreter, Jin Soo Kim said he began working on a tablet in October 2009, months before Apple launched the iPad in January 2010. Kim recounted the rationale behind different design choices for the Galaxy Tab 10.1. The screen, for instance, was set at 10.1 inches both to maximize its size and contain manufacturing costs.

"I really enjoy what I do as a designer," Kim said. "I am proud of what I do."

Asked by Samsung attorney John Quinn whether he copied the designs of any other company, Kim said: "I have not."

Apple attorney Harold McElhinny showed Kim internal Samsung emails, referring to a meeting between Samsung and Google executives.

At the meeting, Google told Samsung executives they should redesign its early tablet because it too closely resembled Apple's iPad, according to the February 2010 emails. Google created the Android operating system, which runs on the Samsung phones and tablets at issue in the lawsuit.

Kim said he did not attend the Google meeting and was not briefed about it by his colleagues.

The nine-member jury is scheduled to begin deliberations next week.

The case in U.S. District Court, Northern District of California, is Apple Inc v. Samsung Electronics Co Ltd et al, No. 11-1846.