Vodafone's board is set to meet today to consider a proposed $13 billion-plus offer for Hutchison Essar, the fourth biggest mobile operator in India, in a move likely to spark a bidding war with Reliance Communications.

The world's leading mobile phone operator by revenue is due to decide whether to press ahead with what would be the largest offer to buy an Indian company.

Vodafone executives plan to table an offer in person tomorrow to Canning Fok, managing director of Hutchison Whampoa, and Ravi Ruia, vice-chairman of Essar, who are both scheduled to be in London.

A Vodafone bid would underline the group's ambitions to boost slowing revenue growth in its core European businesses by buying assets in emerging markets.

Arun Sarin, Vodafone's chief executive, last month said he was interested in "selective acquisitions". Vodafone declined to comment last night.

Foreign ownership restrictions in India prevent Vodafone from holding directly more than 74 per cent of Hutchison Essar, which means it may have to relist a minority stake in the operator or find a friendly Indian company for the remaining 26 per cent.

An acquisition would give Vodafone control of a key player in the world's fastest growing mobile phone market.

In October, 6.7 million new subscribers brought India's total to 136 million, compared with China's 5.9 million additions and 449 million total customers.

A Vodafone bid would probably trigger a sharp riposte from Anil Ambani's Reliance Communications. As the second biggest operator in the Indian market, Reliance would be able to exploit big synergies with Hutchison.

One banker familiar with the situation said: "Vodafone is serious about Hutch Essar, so is Reliance, and there may be plenty of others to come."

Hutchison Essar is 67 per cent owned by Hutchison Telecom International and 33 per cent by Essar, a diversified conglomerate with shipping, steel and oil interests controlled by the Ruia family.