Alliance Boots boss Stefano Pessina will hold an 18% stake in US drugstore chain Walgreens once the two companies fully merge.

Pessina already had an 8% stake in Walgreens but will receive more shares now the drugstore has revealed it will go ahead with the full merger, valuing his stake at around $10bn (£6bn), according to the Telegraph.

Walgreens is valued at $57bn (£33.8bn) on the New York Stock Exchange.

Walgreens yesterday revealed it will buy the remaining 55% of Alliance Boots it does not own already. The deal will complete in the first quarter of 2015. It will pay $5.3bn (£3.14bn) in cash and 144 million in new shares. Pessina is expected to take between 120 million and 130 million of the shares.

In the first phase of the deal in June 2012, Walgreens acquired a 45% stake for $4.6bn (£2.73bn) in cash and 83 million shares, with 76 million of the shares going to Pessina.

Pessina will have also received roughly $188m (£111.6m) in quarterly dividends from Walgreens since becoming a shareholder in 2012. He did not take any dividends as a shareholder in Boots.