Microsoft said in a statement the completion of the deal will mark the first step to bring Microsoft and the Nokia devices and services business together.

"We are nearing the final stages of our global regulatory approval process. To date we have received approvals from regulatory authorities in 15 markets on five continents. Currently, we are awaiting approval confirmation in the final markets," Microsoft General Counsel and Executive VP (Legal and Corporate Affairs) Brad Smith said.

This work has been progressing and the firm expects it to close next month, in April 2014, he added.

"Our acquisition will accelerate our mobile-first, cloud-first imperatives. We're looking forward to accelerating innovation and market adoption for Windows Phones and introducing the next billion customers to Microsoft services via Nokia mobile phones," Smith said.

Last week, in another setback for Nokia, the Tamil Nadu government slapped 2, 400 crore tax demands on the company related to devices sold from its Chennai factory.

Nokia has approached the Madras High Court challenging claims made by the Tamil Nadu government.

On March 14, the Supreme Court had refused to lift a restraint on the sale of its Indian assets in a separate case related to payment of tax dues.

The apex court dismissed Nokia's plea against a Delhi High Court order directing its parent company to give an undertaking it would fulfill the conditions related to payment of tax dues.

The apex court's decision not to interfere with the high court order had put hurdles for Nokia transferring its Chennai plant, which is a part of the deal with Microsoft.

Nokia's Chennai factory employs about 8,000 people, 20 percent of them women, and about 30,000 sub-contractors.

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