The European Commission has suspended transactions, except for allocation and surrender of allowances, in all EU Emissions Trading Scheme (ETS) registries until at least 26 January 2011.
According to a statement, the measure has been taken in view of recurring security breaches in national registries over the last two months.
Following the first security breach in early 2010 the European Commission says it has worked with national authorities responsible for registries to ensure that adequate security measures are put in place in all registries.
Introduced in 2005, the registries system has been designed to ensure the accurate accounting of all allowances issued under the EU ETS and to keep track of the ownership of allowances. Those allowances are held in accounts in electronic registries administered by member states (the EU ETS registries).