Paul Kavanagh from the investment firm Killik and co. said that new plans to cap bankers' bonuses will "create a very uncompetitive environment for many banks."
Speaking to Daybreak he added: "Not all pay is irresponsible pay."
As part of a financial reform package, ministers will consider a provisional proposal pushed last week by MEPs and backed by the European Commission.
More top news
Ambulances are struggling to hand patients over to A&E departments within target times, MPs warn.
Zac Goldsmith hopes to be reinstalled as Tory MP for Richmond Park - months after he quit the party and forced an unsuccessful by-election.
Cancer battler Bradley Lowery is back in hospital with "horrendous pain" as doctors fear the disease is progressing.