British Multinational Beverage Company Diageo Plc is planning to increase its majority stake in the Lagos, Nigeria-based brewer Guinness Nigeria Plc to 70 percent, which is worth $200 million.

Diageo, the biggest distiller in the world and maker of Johnnie Walker, plans to offer 175 naira a share to raise its shareholdings in Guinness Nigeria to 70% from 54.3%. According to the report published at Bloomberg, that deal would cost about 41.38 billion naira, or $208 million. Guinness shares spiked 5 percent to 131.48 naira Wednesday after it announced Diageo's plans. This valued the Nigerian brewery at 198 billion naira.

Invest Advocate reported that Guinness Nigeria affirmed Diageo's plans, saying, "At the maximum offer price, the proposed offer would represent a premium of 36 percent  to the 30-day volume weighted average share price and 40 percent to the company's closing share price on September 8, 2015." Guinness also plans to buy shares in the market at a price lower than the N175 per share price offer.

The planned partial tender offer are still subject to requisite regulatory approvals, which includes those in the Nigerian Stock Exchange, as well as the Nigerian Securities and Exchange Commission.

Guinness Nigeria, however, advised its shareholders that any offer is not yet certain, including the prices and the terms. The formal offer documentation will be given to shareholders as soon as the deal gets the proper approvals.

On September 9, Guinness Nigeria' share price closed with an increase of 5 percent to N131.48 from N125.22, which means it gained N6.26 per share. As the second biggest brewer in the country, Guinness Nigeria reported September 7 that its full-year profit dropped 19 percent due to weak economic growth in the continent, which hurt the sales of alcoholic beverages. Nigeria is also badly hit by the crude price crash, as government revenues constantly slowing down, and the public sector workers are not paid for months.