England one-day international Jos Buttler is expected to join Lancashire at the end of the season.
Division Two champions Lancashire have confirmed that keeper Gareth Cross has been released and it is understood that is to make way for the Somerset man.
Buttler has been in a long-running battle for the gloves with Craig Kieswetter at Taunton. England's ODI selectors have gone for Buttler behind the stumps, but Somerset opt for Kieswetter.
On the departure of long-serving Cross, Lancashire's director of cricket Mike Watkinson said: "Gareth has been a valuable and passionate member of our squad over the last eight years and played a key role in the title-winning team of 2011.
"The club felt the time was right for him to look elsewhere to progress his career and we wish him well."
Head Coach Peter Moores added: "Gareth has been at the heart of the team over the last few seasons and is Lancashire through and through. He moves on with our best wishes and an appreciation of all the hard work he has put in.
"He still has much to offer the County game and I'm sure given the opportunity he can use the experience gained at Lancashire to move his game forward."