Qatar National Bank (QNB), the Gulf’s largest bank, has disclosed its purchase of a 12.5 % stake in pan-African lender Ecobank, and likely also making QNB the second-largest shareholder in Ecobank after South Africa’s state-owned Public Investment Corporation.

No value for the transaction was given in QNB’s statement, but the deal involves 1.77 billion ordinary shares and the conversion of 732.3 million convertible preference shares, and based on Ecobank’s recent share pricing, the stake should be worth in excess of $223m.

QNB has expressed its intention to become the largest bank in the Middle East and Africa by 2017, as domestic competition in its home market reduces the profitability of lending, and the bank now boasts the second largest regional assets after Standard Bank.

At the start of the year, the bank’s CFO, Ramzi Mari, announced that the lender was looking for acquisition targets in sub-Saharan Africa as one of several ways to help achieve that goal.

For Ecobank, which is listed in Lagos and based in Lome, the new cash will help the lender meet the increasingly international capital requirements in Africa’s largest economy.

Ecobank expects its capital adequacy ratio to hit 18.7% of assets by year-end, after debt conversions to equity, up from 17.5% in the first six months of the year, said CEO Albert Essien. The minimum capital adequacy ratio for financial institutions in Nigeria is 16%.

The bank is the second largest in Africa after Standard Bank, with an asset tally of $23.4bn as of June.

The value of stock in the African bank has also risen by 5% this year, compared with a 0.8% decline in the Nigerian Stock Exchange All-Share Index; while QNB shares have risen by 22% this year, compared with a 35% gain for the QE Index.

QNB bought the Ecobank shares from the Asset Management Company of Nigeria (AMCON), which in turn acquired the stake after the pan-African lender merged its Nigerian operations with a failed lender named Oceanic Bank that AMCON earlier helped recapitalise.

Last month Essien also informed Reuters that he expected South Africa’s Nedbank to convert a $285m loan into shares in Ecobank before the end of the year and top up the conversion amount with $206m to give it a 20% stake in Ecobank.

QNB Capital, a unit of Qatar National Bank, is also believed to be a strong contender to arrange Kenya’s first Islamic bond issue after it was the main Middle Eastern part in the county’s debut $2bn-Eurobond in March, alongside largely Western and African parties.