Progressive Conservative Leader Jason Kenney says the unity discussion group hasn't yet reached a deal on joining the Wildrose and PC parties.
When members of the group were announced in March, the public was told it would take four to six weeks to reach a deal. The six-week deadline was Friday.
In his first news conference in more than a month, Kenney said there never was a hard deadline for the group to complete its work.
"We were setting that as an aspirational goal for the unity discussion group," he said. "We wanted to set an ambitious timeline.
"We're working on it as we speak. Stay tuned. We're very close. The differences have narrowed considerably. We should have news for you in the not-so-distant future."
Wildrose Leader Brian Jean has said any unity deal must be approved by at least 75 per cent of his party members.
The Progressive Conservative party doesn't specify any number in its constitution, so Kenney said the threshold is assumed to be 50 per cent plus one.
He said he expects a vote would garner a higher approval rating but declined to state what number would be sufficient.
"I'm not going to pick a random number," Kenney said. "To make such a big change, we need a large mandate. We started with a big mandate for this on (the day of the leadership vote), and I expect to see a large mandate, should we get to a referendum."
Grassroots advisory panel
Jean released a video Friday afternoon with his response to the discussion group's progress.
The Wildrose leader said the group has made "significant headway" and expressed optimism there will be a deal for members to vote on.
He said 60 grassroots members are advising the five Wildrose members on the unity discussion group about what issues are important to them.
"The most important thing that we can remember throughout all of this is that unifying conservatives cannot be based on a principle of gaining power for power's sake. It must be more than that," Jean said.
"It must be about bringing together common-sense conservatives in overwhelming numbers behind a principle of good government."
Kenney has kept a low profile since late March, when he told the Calgary Herald he supported parental notification when students join gay-straight alliances, except when parents are known to be abusive.
Kenney told reporters Friday he has met with party members across the province and done "dozens" of media interviews since then.