Sony Ericsson has delivered a major blow to the future of Symbian, declaring that it will not release any products with the operating system for the time being.
The handset maker had used Symbian throughout its mobile range, but has moved to Google's Android operating system with the Xperia X10 and its variants.
"We are still a member of the Symbian Foundation and follow the development of the platform, but we have no plans for the time being regarding new products on Symbian," Sony Ericsson said in a statement.
It now looks like Nokia will be the last major phone manufacturer to stand behind Symbian, putting its faith in Symbian^3 for its much-anticipated N8 handset.
Symbian is still the most widely used smartphone operating system, although its stagnation in recent years has meant that Nokia and Sony Ericsson have suffered at the hands of competitors.
The Symbian Foundation has members including handset manufacturers, chip makers and mobile operators. But this has not stopped it becoming increasingly irrelevant as devices running Android, Apple's iOS and RIM's Blackberry OS have eaten into its market share.
Even Nokia has hinted at a life without Symbian with the Linux-based Meego operating system that it is developing in partnership with Intel.
Gartner analyst Nick Jones suggested in a blog post that Sony Ericsson's departure effectively means that "the brave Symbian open source experiment has failed".
"In my view we need to separate Symbian's problems from the Symbian Founda tion's problems," he said.
"Symbian can be fixed if Nokia acts very rapidly. Symbian 4 needs to be nothing less than outstanding. If it's not, Nokia may have to face a difficult decision about whether to abandon Symbian entirely and rebuild Ovi in a new form."
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