Production is being switched to Poland
Television production is ending on Thursday at a Plymouth factory with the loss of 270 jobs.
The closure of Toshiba's Ernesettle plant, which has been producing TVs since the 1960s, comes as production is moved to Poland.
The firm blamed a "fiercely-competitive market" for the closure.
It marks the end of mass TV manufacturing in the UK, a technology the country invented, and has been described as a "body blow" to Plymouth.
Tim Jones, chairman of Devon and Cornwall Business Council, said the move would have a serious impact on the city.
Mr Jones said: "This is a trophy company for the city, a global company which has become part of the family of manufacturing companies in Plymouth.
"The city was struggling to meet demand for jobs.
"For every job that comes up there is a queue of vacancies, so not only do we lose a fantastic company, but all the skills of those employed there," he added.
"We could lose another 150 jobs as a direct consequence to suppliers."
But Mr Jones said that there had been a "far greater level of stability" among companies in the city in the past few weeks.
"We haven't got back to the point of a growing economy, but the magical word confidence is starting to return," he said.
"Plymouth is a great city with a great future and we need to make sure we are exploiting those areas in which the city has great skills and expertise."