Cainiao Network Technology Co., the logistics arm of Alibaba Group Holding Ltd., has started preparations with banks for its Hong Kong initial public offering, people familiar with the matter said, paving way to be the first of the Chinese tech firm’s six business units to go public.

Banks including China International Capital Corp. and Citigroup Inc. are working with the company to prepare for the first-time share sale, the people said. The firm is targeting a listing as soon as the end of this year, said one of the people, asking not to be identified as the information is private. Cainiao is currently valued at more than $20 billion, the people said.

Cainiao hasn’t decided on the IPO size, while the timing is still subject to change depending on market conditions, the people said. A representative for Cainiao said the company doesn’t have a clear plan and timeline for an IPO. A representative for Citigroup declined to comment, while a spokesperson for CICC didn’t immediately respond to requests for comment.

Alibaba this week unveiled plans to split its $250 billion business into six main units encompassing e-commerce, media and the cloud. Each business will explore fundraising or IPO at an appropriate time. The tech mammoth will consider gradually giving up control of some of its main businesses, Alibaba CEO Daniel Zhang said on a conference call on Thursday, but declined to specify a timeline for any IPOs.

Cainiao, which means rookie or amateur in Chinese, promises to deliver packages in China within 24 hours and anywhere else in the world in 72 hours, according to its website. It directly operated fifteen overseas sorting centers as of the end of last year, and partners with more than 500 logistics companies globally.

The Alibaba arm’s revenue, after inter-segment elimination, rose 27 percent on a year-on-year basis to 16.6 billion yuan ($2.4 billion) for the three months ended Dec. 31, according to a statement last month. Upgrades in consumer logistics services and international fulfillment solutions contributed to the growth.