Sony-Ericsson has announced that Najmi Jarwala, its president in the US, is to leave the company.
The telecoms joint venture said in a statement that Jarwala would leave at the end of this month to "pursue other career opportunities". However, the announcement follows earlier warnings from the firm that first-quarter revenues were likely to be disappointing.
The company said that weak consumer demand in the UK would contribute to a loss of about €400m (£368m) in its European operation. In Jarwala's territory of North America, Sony-Ericsson expects to see a loss of between $460m and $528m (£312m and £358m).
"Under Najmi's leadership we have redefined our North American strategy, built operational excellence and strengthened our total presence considerably in this very important market," said Dick Komiyama, president of Sony Ericsson.
"We are sad to see him leave Sony Ericsson after more than three successful years, but at the same time we wish him all the best for his future."
Jarwala added: "We have introduced an increasing number of new products, grown market share, built operator relationships and, perhaps most importantly, laid the foundation for North America to play a key role in the long-term growth and success of Sony Ericsson."
However, despite continued assurances that both companies remain committed to the joint venture, rumours abound that a split may be imminent.
Merran Wrigley, vice president and head of external communications at Sony-Ericsson, who acts as UK spokeswoman, insisted that the rumours were "just that".
"We have not seen any indication that either of the parent companies has plans to withdraw, and both are fully committed to the joint venture."
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