Australian Open runner-up Qinwen Zheng will skip the United Cup tournament in what she believes will give her the best preparation for the first grand slam of 2025.

World number five Zheng lost the 2024 Australian Open final to Aryna Sabalenka 6-3, 6-2, but went on to win gold at the Paris Olympics and finish runner-up at the season-ending WTA Finals.

The 22-year-old was due to represent China at the United Cup, starting December 27, but announced on Instagram she will skip the event.

"After the long season that 2024 was for me, I need a few extra weeks of rest, recovery, and good training to get ready for the new season," Zheng wrote.

"I had such a fantastic time at the United Cup in January of this year, and therefore will miss the event greatly.

"Still, I'm so excited to be back in Australia soon and I will see you all in Melbourne in a couple of weeks."

China begins its United Cup campaign against Brazil in Perth on Friday, with Zheng's withdrawal leaving world number 175 Gao Xinyu as China's top-ranked woman.

World number 45 Zhizhen Zhang is China's top-ranked male at the event.

The Australian Open begins on January 12.

AAP