It will operate five trains per day each way between Newcastle and Edinburgh, starting in December, with improved connectivity between Northumberland stations.
Dennis Fancett, chairman of the South East Northumberland Rail Users Group (SENRUG), said: “This is an excellent initiative representing a useful compromise or stepping stone between what we have today and where we aspire to be.
"Most importantly, it can be implemented quickly, from this December. It utilises otherwise empty stock movements since TPE trains, currently terminating at Newcastle, are in fact maintained at Edinburgh.”
But he stressed: “Welcome though it is, it is not however the long-term solution, and is essentially two halves of entirely separate good initiatives that SENRUG is campaigning for, joined together to create a useful though not entirely logical solution.
"In particular, these TPE trains will not be connected to their Newcastle - Liverpool service, so are not providing any direct connectivity between Northumberland stations and Durham, York, Leeds and Manchester.
"Neither is the service hourly, as originally promised for the December 2019 launch. Nor will it easily facilitate further smaller stations along the East Coast Mainline route such as Belford to be opened.
"It is however, a good way of tiding us over until we get the new services we need organised properly, which could take 2-3 years of further planning.
"I want to place on record our thanks to each of The Rail North Partnership, Transport Scotland and TransPennine Express for swiftly concluding these negotiations which make this new service possible, with a start date less than three months away.
“Longer term though, we want to see the Transpennine Express service as a true “semi-fast”, running hourly in each direction, including weekends, continuing on through Newcastle to either Manchester or Liverpool. Stops would be most likely limited to the key market towns of Morpeth, Alnmouth, Berwick, and a station in the Scottish Borders.
“This therefore needs to be augmented by realisation of Northumberland County Council’s "Restoring Your Railways" bid for a full electric local stopping service, again hourly in each direction, seven days a week, which would also serve Pegswood, Acklington and Chathill, which would have capacity for further new or re-opened stations to be added. The case for Belford is already developed.
"Other possibilities include Beal and Warkworth and to the south, SENRUG envisages a new interchange station with Metro at Benton East, once a through Metro service between Airport and Northumberland Park is running, to give simple single station interchange between Airport and Cramlington, Morpeth and North Northumberland. Plus an extension beyond Newcastle to a new station at Team Valley (Low Fell).
“So there is a lot to continue to campaign for, but the announcement represents a very welcome step in the right direction, for which we are most grateful."
He added: “We are certain this new service will help re-invigorate our local economy, creating easier access to jobs from Cramlington and Widdrington, and enhancing the tourist potential of towns like Berwick.”