The government is likely to approach parliament next month to water down retrospective tax rules that damaged investor confidence, two finance ministry officials said on Monday, in a move that may help settle UK-based Vodafone Group Plc's long-runnning $2 billion tax dispute.

Vodafone, the largest overseas corporate investor in India, has repeatedly clashed with Indian authorities over taxes since it bought Hutchison Whampoa's local mobile business in 2007.

The government was heavily criticised by the corporate sector for introducing the tough tax rules last year at a time India was suffering a sharp economic slowdown and trying to encourage investment.