Plaid Cymru is holding a conference in Carmarthen to discuss the way forward for Wales following the Brexit vote.
Leader Leanne Wood said Saturday's event would give members an opportunity to have their say on party strategy.
She is expected say her party will stand up or remain voters and show leave supporters Westminster holds Wales back, not Brussels.
Welsh Conservative leader Andrew RT Davies said Carwyn Jones and Ms Wood were "unable to accept" the leave vote.
In an article for Click on Wales, Mr Davies said Wales could be prosperous post-Brexit.
Both Mr Jones and Ms Wood campaigned to stay in the EU, whereas Mr Davies voted leave.