THIRTY technical issues still need to be resolved to the satisfaction of safety watchdogs before the design of the proposed Sizewell C nuclear reactors is given conditional approval, it has been disclosed.

The latest report from the Office for Nuclear Regulation (ONR), the UK nuclear safety and security watchdog, reveals that only one of 31 issues identified in the design of the proposed European Pressurised Reactor (EPR) has so far been resolved.

EDF Energy wants to build two EPRs to form Sizewell C at an estimated cost of �6bn.

Two reactors of the same type are also scheduled for Hinkley Point in Somerset

However, the technical features of the reactor, which is designed by French engineering company Areva, first have to be approved by the ONR, which is under pressure to meet an end-of-year deadline for the Government to be able to announce that no technical hurdles lie in the path of the construction of the new reactors.

Safety inspectors are involved in a process called generic design assessment (GDA) aimed at resolving concerns.

The Nuclear Free Local Authorities organisation is urging the Government to refrain from putting unnecessary pressure on the ONR to speed up the process. It says it fears nuclear safety could be compromised for political expediency.

Pete Wilkinson, a Suffolk-based environment consultant who has advised Government departments on a range of radioactive waste issues, said the ONR was struggling to meet the Government's deadline. 'It is having to resort to pushing back the resolution of some key issues. The net effect is that critically-important generic design assessments are being delayed to allow a political deadline to be met,' he said.

An ONR spokesman said the timescale for resolving outstanding issues was largely dependent on the work programmes of EDF and Areva. The two companies needed to provide the ONR with 'timely and right first time responses requiring minimal further interaction', he said. 'We're ready to do everything we can to draw our conclusions of the GDA issues by the end of 2012,' the spokesman added.