There is an "unprecedented sea" of new regulation for banks, Baudouin Prot, BNP Paribas chief executive, told CNBC in an interview at Davos.
Regulators need to make sure they're not "overloading" banks, and that regulations are enforced around the world, he said.
Prot, head of France's biggest bank, said BNP is "comfortable with" the new capital requirements under Basel III and will be ready without a need for more capital.
Mergers and acquisitions between European banks could be made more difficult by the new regulations, Prot believes.
"BNP is the right size," he said. "Bigger is not always better and you need solid banks."
Prot is "cautiously optimistic" about Europe and said there has been an improvement in investors' mood this year.
He praised the December long-term refinancing operation (LTRO) by the European Central Bank and said he thinks February LTROs will see a smaller take-up.
Mario Monti, the leader of the Italian technocratic government, is "doing an excellent job" according to Prot.