The value of shares in Alibaba.com, China's largest business-to-business internet portal, almost doubled in their first day of trading in Hong Kong today.

By close of trading the company had reached a market capitalisation of $25.7bn.

The Alibaba portal allows businesses to post details of products for sale which potential buyers can search and use to contact sellers. Basic membership is free.

The eight year-old company has long relied on substantial investments from foreign firms including Yahoo, Cisco and Japan's Softbank which has a 30 per cent stake in the parent Alibaba Group.

These investments have enabled Alibaba to continue expanding without seeking a public listing. The company claimed almost $130m in revenue in the first half of the year.

The Alibaba Group had already generated $1.5bn from new share sales by the start of today's initial public offering, according to local press reports.

With limited opportunities to invest in strong Chinese internet firms, the IPO proved extremely popular and the public portion was more than 257 times oversubscribed.

Alibaba founder and chairman Jack Ma told reporters in Taipei today that, building on its strong position as China's largest B2B portal, Alibaba has its sights set on becoming the clear leader in Asia, and perhaps eventually the world.

The Alibaba Group also includes Taobao.com, China's leading consumer-to-consumer auctions site, which leads eBay by a considerable margin in the country.

The group recently established Alipay, an online payment system broadly similar to PayPal.