Ameriprise Financial, the parent company Columbia Threadneedle, has acquired the European asset management business of BMO Financial Group for £615m — a deal which will add more than $120bn to the amount of money it oversees in the region.

The acquisition, expected to close during the final quarter, will significantly boost Columbia Threadneedle's assets under management to around $671bn globally, with assets managed in Europe, the Middle East and Africa accounting for 40% of this total.