Plans to bring MotoGP to the Welsh valleys took a huge knock this afternoon when the Welsh Assembly said it could not justify funding the Circuit of Wales project.

The scheme, which had promised to bring 6000 jobs to the Gwent area, will now have to rely on private backing - one being insurance firm Aviva - if it is to make any further progress.

Economy minister Edwina Hart said the Welsh Government were being asked to underwrite Aviva Investors’ entire £357.2 million investment in the scheme, which she said would carry an “unacceptable risk”.

Aviva's money would have allowed work on the track, which aims to bring thousands of bike fans for motor sport events like the MotoGP and employ up to 6,000 people in the south Wales area.

Ministers agreed to provide grant aid of £16m to support job creation if the project goes ahead.

But the sticking point came over the Welsh Government being asked to provide a financial guarantee to the privately-funded project. Ministers took legal and financial advice, including from outside, and it was after final external advice that Mrs Hart made her decision.