The president of the Alberta Progressive Conservatives resigned Friday only weeks after Jason Kenney won the party leadership on a platform of forming a new united conservative movement with the Wildrose.
Katherine O'Neill said she needs a break after two years of working to rebuild the PCs following the party's devastating defeat in the 2015 provincial election that swept the NDP into power.
O'Neill said she is leaving on good terms with Kenney and was not asked or pressured to step down.
"I have had a very good working relationship with Mr. Kenney since he won," she said in an interview.
"It has been a very respectful collaborative relationship and, for me, I just felt that this was that perfect time as we are just about to really kick up the unity discussions."
Kenney paid tribute to O'Neill in a post on social media, thanking her for years of hard work under challenging circumstances.
He praised her for helping to rebuild the party's 87 constituency organizations and raising money to help pay off part of its debt.
"Rather than walking away after the (2015) election defeat, she dug deep and with others brought leadership to the party at a time of real adversity," Kenney wrote.
"The PC party is in a better financial position, with a much larger membership and more active constituency organizations than a year ago thanks in part to Katherine's leadership and hard work."
Kenney said he will work with the PC executive in the coming weeks to choose her successor.
O'Neill, a mother of three young children, said she wants to spend more time with family.
"I'm not leaving for good," she said. "Just taking a breather and recharging my batteries."
On March 20 Kenney met with Wildrose Leader Brian Jean to discuss what steps the two conservative parties should take toward a potential merger.
They agreed that a team of members from both parties will try to come up with a draft unity agreement by the end of this month.