OSLO: Norway's largest bank DNB said on Monday it had secured a 74.9% stake in domestic rival Sbanken and raised its bid by almost 5% in order to further increase its holding.

DNB's offer, which is subject to regulatory approval, now stands at 108.85 crowns, valuing Sbanken at 11.6 billion crowns ($1.4 billion).

"This is the offerer's best and final offer price," DNB said in a statement, adding it would expire on June 14.

Shareholders who accepted DNB's bid, including those who already agreed to the offer, are eligible to receive the higher price.

Sbanken's biggest owner, investment fund Altor, had agreed in April to sell its 25% stake to DNB.

Sbanken's shares rose 4.9% following the news to close at a record high 107.8 crowns, while DNB's shares fell by 0.1%.

The takeover will increase DNB's share of the Norwegian mortgage market to an estimated 27% from about 24% while also strengthening its asset management business.

DNB was advised by in-house broker DNB Markets while Sbanken was advised by Arctic Securities.