Henderson Group on Wednesday said it is taking steps to stem outflows at acquisition target Gartmore Group, after Gartmore fund investors pulled another £810m in just seven weeks.

Henderson chief executive Andrew Formica said both Henderson and Gartmore teams are reassuring Gartmore clients that at least 12 Gartmore fund managers controlling around 84% of Gartmore assets have already agreed to join Henderson, and said he's confident that new money will flow into Gartmore funds once investors see that they have been smoothly integrated with Henderson.