President Trump's decision earlier this month to withdraw the United States from the Paris Accord on climate change has only boosted the appetite for driving the sustainability agenda forward, according to the head of Nordea Asset Management.

"I think it has given more momentum to it because I think his voters and our clients will now much more clearly realize that they need to take action and they need to make sure that this is on top of the agenda of both banks and politicians - and the media as well," Nils Bolmstrand, chief executive officer (CEO) of Nordea Asset Management, told CNBC at FundForum International in Berlin on Tuesday.

The Paris agreement, formally signed on behalf of the U.S. by former President Barack Obama in September 2016, is a global initiative aimed at keeping temperatures around the world from rising more than 2 degrees Celsius. This level has been identified by scientists as a threshold above which further rises could have potentially disastrous and irreversible effects.

Following the president's announcement, 12 states, as well as Puerto Rico, have undertaken a pledge to pursue policies that uphold the country's original commitments to the the Paris Agreement.

The same prioritization of sustainability initiatives seen in these states is reflected in the preferences of the client base of Nordea Asset Management, which is part of Europe's largest financial services firm Nordea Group, according to its CEO.

"To the same extent that President Trump is now seeing that his electorate is actually making its own decisions and states are choosing to stay in the Paris Accord, I think this for us is a client-driven action," asserted Bolmstrand.

"Clients are today voting with their feet and they're actually putting money into sustainability where they haven't so much historically. I think this for us is an important change that has happened," he added.