Finnish-Swedish banking giant

Nordic Baltic Holding

said Monday it has inked an agreement to buy Danish Unidamark in a stock deal valued at more than $3 billion.

Nordic Baltic Holding, formerly

MeritaNordbanken

, said it would pay 12.704 shares per Unidanmark share, valuing Unidanmark at 3.23 billion euros ($3.12 billion), or 69.1 euros ($66.50) per share, a 15% premium over Unidanmark's Friday close. In trading Monday on the

Copenhagen Stock Exchange

, Unidanmark shares jumped 62 Danish krones, or 14%, to 510 krones ($66.04).

With total assets of 186 billion euros ($179.7 billion), the new group will be bigger than Swedish

Handelsbanken

, which has a balance sheet total of some 111 billion euros.

Nordic Baltic was formed in 1998 through the merger of Finnish Merita and Swedish Nordbanken.

The merged group will have a combined market capitalization of 15.6 billion euros and 9 million customers, NBH said.

NBH's owners will hold 70% of the new group and Unidanmark's will get 30%. Unidanmark will bring NBH roughly one-fifth of Denmark's domestic lending and deposits. Unidanmark will also bring to NBH Norwegian insurer

Vesta

, which Unidanmark bought in December for some $630 million.