Chinese e-commerce group Alibaba has reportedly acquired a stake in online shopping company ShopRunner, managed by former Yahoo chief Scott Thompson.

The acquisition is part of a string of investments planned by the world's largest e-commerce group, ahead of its proposed initial public offering (IPO), the Financial Times reports, citing sources close to the matter.

Alibaba will pay $75m (£48m, €56.2m) for a minority stake in ShopRunner, which offers fast shipping services like those of Amazon through its "prime" membership. Other terms of the deal are yet to disclosed.

California-based ShopRunner offers unlimited two-day delivery from nearly 80 retailers including Toys-R-Us Inc and MackMall.

Alibaba's move is part of its plan to expand its business outside China ahead of its potential $70bn Hong Kong flotation expected to take place at the end of this year.

According to the Financial Times report, the investment will strengthen the existing long-standing relationship between Alibaba and Yahoo, a major shareholder in the company.

The FT also reported that Joe Tsai, vice-chairman of Alibaba, has been seeking investments to increase the company's know-how about US retail markets.

This is Alibaba's second recent investment in a US e-commerce company, following a June investment of $170m in sports retailer Fanatics.

"The US is a very big and important market and such strategic investments will help the company understand better how the retail business operates in the US," the FT quoted a source as saying.

After going private last year, Alibaba, which dominates China's e-commerce market, acquired a number of businesses to boost its profile.

Earlier, Alibaba bought a 28% stake in Chinese digital mapping company AutoNavi for $294m. The company has also spent $586m on an 18% stake in Sina Corp's Weibo business.

On the back of its acquisitions, the company reported strong earnings and revenues. According to a regulatory filing by major shareholder Yahoo, the Alibaba Group reported a 171.1% rise in net profit as revenue climbed 84% to $642.2m in the fourth quarter.

Alibaba is likely to use the funds from its proposed IPO to snap up a raft of companies in a bid to expand its mobile phone services.

In May, media reports surfaced that Credit Suisse would take a leading role in the planned IPO.