James Ashby denies attempting to orchestrate One Nation preference deal with Labor ahead of Victorian election

Pauline Hanson's chief strategist has rubbished suggestions he has been attempting to orchestrate a preference deal between One Nation and Victorian Labor ahead of the state election.

Two senior Labor sources have told Guardian Australia that James Ashby has contacted the party's campaign headquarters in recent weeks, including making calls to their senior leadership on 24 and 26 October.

But Ashby told Guardian Australia on Thursday his calls were not about preference negotiations, but about leaders' debates.

"I wanted to know whether they were participating in the debates. That's all it was," he said.

"I was trying to get a grasp of who was holding back these debates because the dates kept changing. My interest was simply in finding out exactly who was in and who was out, and whether or not they were being deterred from being involved because One Nation were involved."

Ashby was blunt about the suggestion he could be seeking a deal with premier Ben Carroll's campaign.

"There's no preference deals. I'm not interested in talking to them about preferences. We want them gone. That's why we put them last."

One Nation's Victorian leader, Warren Pickering, was pictured having coffee with the Labor operative Andrew Landeryou in Melbourne's CBD on Thursday morning.

Landeryou – the partner of the late Victorian Labor senator Kimberly Kitching – is associated with the party's right faction and is a lobbyist.

The Liberal campaign has seized on the image, suggesting that One Nation and Labor could make a preference deal. This is despite Labor seeking to make the prospect of a Liberal minority government a factor for voters ahead of the poll, suggesting the opposition leader, Jess Wilson, could be reliant on One Nation to hold power.

Guardian Australia has contacted Pickering and Landeryou for comment.

In recent days, billboards warning voters of a Liberal-One Nation coalition have been erected across a range of critical seats, including in suburban Bentleigh and Mordialloc, in the Melbourne sandbelt.

Nationally, Labor hopes the prospect of Hanson's populist movement having an influence on government in Victoria could scare voters into reconsidering moves away from the major parties.

Victorian Labor sources insist the party is not negotiating with One Nation out of principle, despite Ashby's attempts to make contact.

"Preferences are negotiated by the Labor party," one insider told Guardian Australia. "The Labor party is not speaking to One Nation.

"The Liberal party should preference us before One Nation, just like John Howard did."

A second source said Landeryou had "no involvement whatsoever" with the party's preferences ahead of the 28 November poll.

Landeryou is a registered lobbyist in Victoria and the chief executive of Critical Issues Group, which pitches itself as "counsel at the intersection of capital and consequence".

A longtime political player, he is close to the former Labor leader Bill Shorten and has a history as a political blogger and operative.

Asked on Monday if One Nation would support a Labor majority government if it agreed to make the cabinet decisions more transparent, Pickering told reporters: "We are not going to engage in speculation about preferences or supply and confidence at this point.

"One Nation is here to win, and we will get this done, whatever the disposition of the parliament."