In a meeting with the Minister for Portsmouth, Michael Fallon, the unions – Prospect, GMB, Unite and UCATT – stressed the immediate crisis facing the city, with the loss of 940 jobs in the shipyard and further job losses at Rolls Royce and IBM.
Prospect negotiator John Ferrett said: "I challenged the minister directly to approach BAE Systems and call on the company to halt the redundancy programme. Michael Fallon said he would do this, but continued to stress that it was for the company to decide when people should be made redundant.
"The unions pointed out the madness of effectively closing the yard by September, just at the point where Scotland may vote for independence. The uncertainty around the outcome of referendum is another strong argument for putting the redundancies on hold.
"Since UK government policy is not to build complex warships outside the UK, a yes vote in the referendum would leave Portsmouth as the only UK shipbuilding facility outside Scotland."
While welcoming the prospect of new businesses in Portsmouth that would use the skills and capabilities of shipyard workers, the unions stressed these would only be viable if there was a workforce ready to transfer into them.
"For that reason the government and BAE Systems should find a way to retain as many skilled workers as possible until the future use of the shipbuilding facility has been determined and alternative uses for the yard have been considered," said Ferrett. "Naval shipbuilding should remain in the city and the government should revisit the 41 options for building future warships drawn up by BAE Systems."
Prospect represents over 300 skilled engineers and other senior professionals working for BAE Systems Surface Ships in Portsmouth naval base.