Ieaun WYn Jones making his announcement on Anglesey Ieuan Wyn Jones has said he will stand down as Plaid Cymru leader in the first half of the assembly’s five-year term.
He said it had always been his intention to leave the role at some point before the next assembly election in 2016.
The announcement follows a poor showing for Plaid at last week’s election when it lost four seats.
Speaking on Beaumaris, Anglesey, he said it had been a “great honour” to lead the party over the last 11 years.
The timetable for his departure means Mr Jones will go some time in the next two-and-a-half years.
In a statement delivered in front of party colleagues, he said the “time was right” for him to make his plans clear.
He said it had been an honour to lead the party and to serve as deputy first minister in the last assembly.
“I have also witnessed many historic and momentous events during that period, not least leading the party into government for the first time in its 86-year history and the referendum on law-making powers,” he said.
Mr Jones was MP for Ynys Mon from 1987 to 2001 and has been the island’s AM since the first assembly in 1999. He first took up the party leadership in 2000.
Last week’s election saw Plaid slump to 11 seats – its worst tally since the assembly was established.
There has been criticism that the party’s campaign was too negative by attacking its former coalition partners in Labour.
Mr Jones said the result was a “disappointment”, adding: “As leader I take my share of the responsibility for those results.
“The party obviously needs time to reflect on the results, look long and hard at our message, our party structures and campaigning abilities.”
He said he was confident Plaid would recover “stronger and better, provided we understand the need to change and modernise”.
An immediate leadership election would not be in the party’s interest because of the need to review the election result, he said.
He thanked his family for their support, including his wife Eirian – “a rock through it all” – and his three children and four grandchildren.
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