European regulators on Tuesday urged the United States and Europe to push through measures agreed by the G20 nations aimed at avoiding future financial crises, saying transatlantic relations were at risk if the effort flagged.

The G20 group of industrial and emerging nations has laid out a raft of measures to improve financial supervision to get a better grip on systemic risk at local and international levels.

At the Euro Finance Week in Frankfurt, European regulators warned that misunderstandings were hampering the effort to improve cross-border cooperation and said U.S. resolve to act appeared to be weakening in some areas.

If we can't have at least the measures that were designed at G20 implemented on both sides of the Atlantic then we need to go back and think again on the relationship, because it's going to be impossible to have trust for the future, Gabriel Bernardino, chairman of European insurance supervisory body, CEIOPS, said during a panel discussion.

Eddy Wymeersch, chairman of the Committee of European Securities Regulation (CESR) said he detected diminishing willingness of the United States to engage in opening the markets on both sides. That's quite frightening, he said.

I'm very much afraid that in the future the transatlantic dialog will become increasingly difficult. It has already become almost inexistent.

At the same time, he said, the United States had become very angry on the measures we are taking, for instance in alternative investments, that we are closing our markets.

The EU's executive European Commission has proposed draft laws to create a European Systemic Risk Board (ESRB), hosted by the European Central Bank, due to be set up next year.

Three new pan-EU supervisory authorities for banks, markets and insurers are to work closely with the ESRB.

The U.S. administration has made a proposal on how to deal with too big to fail banks but is facing opposition. It has also drafted plans to set up a systemic risk regulatory council.

Sharon Bowles, chair of the European Parliament's powerful committee on Economic and Monetary Affairs was more upbeat about transatlantic cooperation and said she was very struck with how much in common there is with the thinking and the political will.

I'm actually optimistic that there is a move to come together. But obviously people are watching one another because nobody wants to be the victim of regulatory arbitrage, she said.

(Reporting by Eva Kuehnen, Jonathan Gould and Edward Taylor; Editing by Jon Loades-Carter)