Alibaba has pushed its highly anticipated initial public offering (IPO) until after the September Labor Day holiday, a source with knowledge of the matter said, as the Chinese online retail company works through the complex process of launching what could the largest-ever US tech debut.

Alibaba, which had targeted an August float, now plans to begin its investor roadshow and price its shares in September, the source said on condition of anonymity because the IPO process was private.

Though the IPO remains on track, the Chinese company wanted to avoid the weeks before Labor Day, when many on Wall Street take off on their summer vacations, the source added.

Alibaba has already begun reaching out to the investment community. It has held at least two rounds of meetings with financial analysts in its hometown of Hangzhou in eastern China, according to a second person familiar with the meetings.

The company, which powers 80 per cent of all online commerce in the world's second-largest economy and handles more transactions than Amazon. com and eBay combined, is expected to garner a valuation of as much as $200 billion.

Many investors expect its IPO to top the $16 billion pulled in by Facebook in 2012.

A representative for Alibaba declined to comment.

Reuters