The proposed merger of Standard Life and Aberdeen Asset Management will create “a world-class investment company”, Aberdeen’s co-founder and chief executive Martin Gilbert has said.

Plans to merge the two firms - creating the biggest asset management firm in the UK and the second-largest in Europe - were announced earlier this month and could be completed as early as September.

Writing in The Telegraph today, Mr Gilbert said the two firms’ “respective investment capabilities and expertise complement each other’s”.

He wrote: “Together, we will become a leading force in five main asset classes – equities, fixed income, solutions, property and alternative assets (such as private equity), with an unrivalled depth of talent of more than 1,000 investment professionals operating in 20 countries. We think that there is significant value for clients in having investment professionals in locations where they have local insights to the investments that they will be making and are able to keep on top of them.

“Both Standard Life and Aberdeen have a powerful belief in active investment management. We know that over time talented managers can deliver far better returns for investors than passive funds. But to do that we need the best people in the industry. Part of the drive behind this merger is to create a group that will attract and retain the most skilled and committed professionals in the industry. Scale will allow us to invest more in our people and the resources they require to give clients what they need.”

Mr Gilbert said the firms’ distribution strengths are also complementary.

He explained: “For instance, part of Aberdeen’s speciality is distributing products globally. Meanwhile, Standard Life has one of the strongest positions in the UK workplace and retail markets.

“This is reflected in our client base. Together, we will have clients in more than 80 countries, but just four of our respective top 50 clients overlap.

“The potential in our combined and strengthened distribution is clear since we have two specialised businesses that can now work with a much broader range of investment capabilities. It is clear from my conversations with clients during the past two weeks that our increased investment capability is an attractive proposition.”

He concluded: “Of course, we can only achieve all the benefits from this merger if we come together successfully. The early signs are really encouraging. There is a lot of mutual respect among the investment teams at Aberdeen and Standard Life and a real will to work together and make the most of their combined expertise. Right now, we are working towards the completion of the merger by the end of September.

“Asset management is at its heart a people business, so it is vital that as our two businesses merge, our people come together into a united team. Both Keith Skeoch, my counterpart at Standard Life, and I are leading by example, by agreeing to be co-chief executives. This is absolutely the right thing for the combined group.

“When I co-founded Aberdeen in 1983, we had just £50m in assets under management. But we had a vision and ambition to grow into a powerful investment group by listening to what clients wanted. We have achieved a lot already but I am as optimistic about that vision and ambition now as I was then.”