Union leaders are delivering a 10,000-name petition to Downing Street urging the government to back plans for a train factory in County Durham.
Hitachi was provisionally awarded a £7.5bn state contract to build express train carriages, with Newton Aycliffe as its preferred location.
The petition calls on ministers not to axe the project in the Spending Review.
Northern regional secretary of the union Unite, Davey Hall, will hand over the petition later.
It is estimated the 1,000-job plant would bring a £660m boost to the North East economy over 20 years.
The project is dependent on Hitachi being granted the Intercity Express Programme Contract in the government's Spending Review, announced on 20 October.
The petition, predominantly signed by people in the communities around Newton Aycliffe, urges the government to endorse the project and pave the way forward for construction work to start.
The scheme would see the government make a small initial investment and commit to buying the high-speed trains produced in County Durham.
The bulk of the £40m start-up costs would be paid by a private consortium led by Hitachi.
Mr Hall said: "The people of County Durham know how important this bid is for jobs and the local economy.
"If the government gives the green light to this contract the investment would put the North East back on the map as a significant train manufacturer for the European market.
"The North East has a long and successful history with Japanese manufacturing and there is a shared commitment to promoting the region."