Liberal Democrat Ms Lynne said the “time is right” to move on after more than 12 years representing the region in the European Parliament.
She made her announcement at the regional Liberal Democrat Party Conference in Birmingham on Saturday. Citing her reasons, Ms Lynne said she found the “relentless travelling” to and from Strasbourg “onerous to say the least.”
Stepping down now would give her successor, Phil Bennion, enough time to make an effective contribution to the current Parliament, she added.
When an MEP stands down, the position is automatically taken by the second candidate on the party’s list at the last election.
Ms Lynne said: “I have thought about this carefully and believe that the time is right. Although I still find the work stimulating and worthwhile, the relentless travelling particularly to and from Strasbourg is onerous to say the least.
“Stepping down now will also give my successor, Phil Bennion, enough time to bed down and make an effective contribution in the remaining two and half years of this Parliament. I am not retiring but want to focus my politics in ways, which do not involve quite so much travelling. I will continue to support the Liberal Democrat party in any way I can. I remain a strong supporter of Nick Clegg’s leadership and his work in the coalition government.”