Rail firm Grand Central yesterday unveiled its timetable for services linking the North to London after track bosses announced they could find space for the new trains.
Network Rail claimed earlier this year that it would be "very difficult" to find space for the Sunderland-to-London services because the East Coast Main Line was already full.
But yesterday it announced it had managed to find space for the services, along with six new GNER trains from Leeds to Kings Cross.
Grand Central responded by revealing the planned times of its trains, which are due to run from December 10. However, GNER is still set to challenge the Office of Rail Regulation's decision to grant Grand Central a licence, with a judicial review hearing set to begin on Monday.
Network Rail chief executive John Armitt announced yesterday: "We have identified 20 new paths on the East Coast Main Line. This demonstrates the enormous will within the rail industry to increase capacity and grow the railway to accommodate ever-increasing numbers of passengers and tonnes of freight.
"We still have some issues to resolve, but we are working through these, and expect to have these paths established and operational as soon as possible." The 20 paths will allow for six trains in each direction from London to Leeds, three to Sunderland and one to Hull.
Grand Central managing director Ian Yeowart said yesterday he still believes there is room for a fourth daily service from Wearside.
"It will be a bit disappointing if we end up with just three to Sunderland when Leeds has 65," he said. And he added it "vindicated" his firm's argument that both Grand Central and GNER could be accommodated on the route.
GNER spokesman Alan Hyde said the decision was "good news".
However, the company, which holds the East Coast Main Line franchise, still believes the decision to award the licence to Grand Central amounts to unfair competition, as firms will pay different track access charges.