More than 1,000 job losses have been signalled and a number of others threatened in a series of announcements which delivered fresh blows to the economy.
Computer Sciences Corporation (CSC) started a formal 90-day consultation with unions on plans to cut 640 jobs, while British Gas said it was planning to close a call centre at the end of the year with the loss of 550 posts.
Meanwhile communications giant Vodafone warned of a reduction in headcount and office locations under plans to buy ailing Cable & Wireless Worldwide for £1.04 billion.
CSC said: "This action is necessary because the IT services market is changing, and our customers want competitive, new services with different contract and delivery models.
"Through voluntary redundancies and redeploying people within other parts of our business, we hope to achieve a significant reduction without the need for compulsory redundancies. Where this is not possible, we will provide support to help ensure that anyone leaving the business does so in the best possible position."
But Unite said the announcement was a "body blow" which had left employees feeling "devastated".
Unison said the planned closure of the British Gas site in Southampton would be a "blow" to the workers as well as the local economy.
The company said: "If we are going to remain competitive and offer the best prices for our customers, we need to reduce our costs. We have therefore reviewed resource levels in our energy business and are now proposing to close our Southampton contact centre at the end of 2012, leading to a reduction of 550 roles.
"If the proposals go ahead, 50 customer services roles currently sited at Southampton may transfer to our site at Chandlers Ford. Our priority now is to support all those potentially impacted by today's announcement to ensure a fair, open and transparent process throughout.
"We recognise that today's news will be very hard for our employees and their families. This has been a very difficult conclusion to reach but we believe it is in the best long-term interests of our business."