As part of the plan, Idea will raise 32.5 billion rupees by selling 326.6 million shares on a preferential basis to companies controlled by its parent Aditya Birla Group at 99.5 rupees apiece.
The deal will increase Aditya Birla Group’s stake in Idea to 47.2 percent from 42.4 percent currently.
Idea further intends to raise up to 35 billion rupees by selling shares, the company said in a statement, adding the options included a rights issue, preferential issue or a share sale to institutions.
In March last year, Idea and Vodafone announced a merger deal to potentially create the biggest Indian phone carrier. The deal is expected to close this year.
As part of the deal, Aditya Birla Group had agreed to buy a minimum of 2.5 percent stake of the merged entity from Vodafone to own at least 26 percent of it.
Aditya Birla and Vodafone will eventually own an equal share of the joint venture, the companies said last year.
Vodafone said in a filing on Thursday it expected the merger deal to be completed during the first half of this year.
Idea shares closed 1.8 percent higher on the NSE index , while Vodafone shares were little changed in London trading as of 1020 GMT . ($1 = 63.4150 Indian rupees)