Plaid Cymru faces “oblivion” if it lurches to the left, one of its MPs will tell party activists later.
Addressing the party’s spring conference in Llangollen, Denbighshire, Jonathan Edwards will warn against basing Plaid’s strategy on the “intricacies of socialist theory”.
He said the warning was a “bit of friendly advice” and not a personal attack on party leader Leanne Wood.
Leader for six years, she is widely seen as being on the party’s left.
Mr Edwards, MP for Carmarthen East and Dinefwr MP, will urge the party “not to respond to the electoral challenges we face from Corbyn’s Labour by basing our political strategy on the intricacies of socialist theory”.
“I fear that road leads to political oblivion,” he will say.
“In the face of an increasingly insular, hostile, right wing centralist Tory party and a hard left statist command and control Labour party – we have to aim for the gaping void in the middle.
“This does not mean abandoning our principles as a party but prioritising our pro-business, environmental, internationalist and law and justice credentials.”
‘Make a difference’
Asked about Mr Edwards’ comments, Dwyfor Meirionnydd MP Liz Saville Roberts told BBC Radio Wales she wanted to focus on matters affecting her rural constituency at a time “when we’re being faced with so many complex, difficult decisions”.
Speaking on the Good Morning Wales programme, she said: “The decisions that will affect our farmers, our fishing industry, in the wider respect, the public sector, the university… people see that this is going to affect their lives, their children, their families.
“And we need to talk about those in terms of how we can actually make a difference rather than an ideology.”
Analysis by BBC Wales political editor Nick Servini
The normally ultra-loyal Jonathan Edwards says his warning on socialist theory is a bit of “friendly advice” and not a personal attack on Leanne Wood.
Be that as it may, the problem is that Leanne Wood has identified herself so much with that ideology, and in a landmark speech in January talked about the “de-centralist socialism” of her party compared with the top-down undemocratic model of Labour.
It also shows how much traction there has been with the comments from Simon Thomas in the last party conference in the autumn that you cannot out-Corbyn Jeremy Corbyn.
This is the first spring conference for Plaid in a long while without an immediate election on the horizon, freeing up senior figures to speak their minds without the pressure of a vote in the offing.