Apple has asked a federal judge in Silicon Valley to add Samsung's new flagship Galaxy smartphone to the list of devices targeted in a patent lawsuit involving Siri personal assistant software.

The motion to amend the lawsuit to include the Galaxy S4 will be on the agenda of a June 25 hearing before US District Court Judge Paul Grewal in the California city of San Jose.

"Apple's infringement theories regarding the S4 are identical to Apple's infringement theories against the already accused products," attorney Mark Lyon said in a motion filed Tuesday on behalf of Apple.

The five patents at issue in the case include two associated with Siri voice-commanded personal assistant in iPhones.

The filing maintained that the patents were infringed by voice-search capabilities in Android software used to power the Samsung smartphones.

Other patents relate to the user interface and manipulating data, according to the filing.

The case is one of many legal battles between California-based Apple and South Korea's Samsung and the trial is not expected to begin until early next year.

In March, a judge overseeing a separate patent case in Silicon Valley cut $450 million from a $1 billion award to be paid by Samsung in a landmark patent lawsuit from Apple, saying a jury had wrongly calculated the damages.

US District Judge Lucy Koh affirmed the remainder of the award, amounting to $598.9 million.

Apple had accused its rival of massive and willful copying of its designs and technology for smartphones and tablets.

Samsung's latest flagship Galaxy smartphone went on sale globally in April.

The Galaxy S4, armed with eye motion control technology that will pause a video when the user looks away, comes with a faster chip and is thinner and lighter than the previous S3 model.

After years of following and refining the iPhone's pioneering innovations -- a strategy that resulted in bitter patent battles with Apple -- Samsung has dethroned its California-based rival to become the world's top smartphone maker.