It will become the second toll road in Britain - following the M6 in Staffordshire - and will run between junctions 23 and 29 of the M4 to relieve congestion on the outskirts of Newport.
The newspaper reports that the Chancellor will agree to guarantee loans for the building of the M4 relief road, but the devolved Welsh government will meet the cost - expected to be around £830 million.
More top news
Popular, passionate and committed but Stuart Wilkie is not wanted in the leadership role that arguably saved Port Talbot steelworks.
It's the warmest day of the year so far! Rhyl hit 16.1C earlier this morning! But it is far from blue skies and blazing sunshine!
Lukasz Pawlowski cut his throat with a kitchen knife as he was due to be sentenced in Havefordwest. He has been remanded in custody.