Michel Barnier, the EU commissioner overseeing financial services, is understood to be drawing up a list of new rules which specifically cover tampering with indices such as EURIBOR and LIBOR, the FT reports.

The plans would create specific criminal sanctions for those that broke the rules, although many of the traders involved in the current scandal are understood to be facing the possibility of criminal proceedings already.

The main part of the plans is to close loopholes which may have made it more easy to manipulate the inter-bank lending rate.

The proposals would likely get the approval of the US, where politicians are furious over the manipulation.

Barney Frank, the US Congressman who drove through an eponymous financial regulation overhaul, told the FT that banks “monkeying” with LIBOR for their own benefit were “outrageous”.

Martin Wheatley, a top regulator in the UK, is also examining the regulatory regime for Libor and a host of other indices that are currently set by unregulated or semi-regulated bodies.