The Anglo-Dutch consumer goods giant Unilever Plc's proposal to invest $5.4 billion (around Rs 29,300 crore) in its Indian arm Hindustan Unilever Ltd (HUL) would be the biggest single foreign investment in the Indian consumer goods sector.

The proposed deal entails the purchase of around 48.7 crore shares of HUL by Unilever at an offer price of Rs 600 a share.

Announcing the open offer, Unilever Chief Executive Paul Polman said, "The long heritage and great brands of Hindustan Unilever, and the significant growth potential of a country with 1.3 billion people, makes India a strategic long-term priority for the business."

In wake of the announcement, HUL shares gained 20 per cent to hit a high of Rs 597 apiece before closing at Rs 583.6 on Tuesday.

Unilever's open offer, which represents 22.52 per cent of the company's share capital, is scheduled to hit the market in the next few weeks as the Anglo-Dutch consumer goods maker has announced that it would publish further details about the open offer on or before May 8 this year.

Unilever's offer is the largest in the Indian capital markets. In 2011, Cairn India launched open offer worth Rs 13,361 crore to raise its stake in its Indian subsidiary. Earlier in 2008, Japanese pharmaceutical giant Daiichi Sankyo acquired 20 per cent stake in Ranbaxy Laboratories in an open offer worth Rs 6,818 crore.