Vince Cable has brushed off the suggestion that he is considering resigning, just four days after calling David Cameron "very unwise".
The Liberal Democrat business secretary said he had "no intention of quitting the Cabinet" as he shared a platform with centre-left politicians including the leader of the opposition, Ed Miliband.
After openly attacking the prime minister's stance on immigration it emerged over the weekend he had encouraged colleges to launch a legal challenge against the government over immigration policy.
His appearance alongside Mr Miliband, former Labour home secretary Alan Johnson, Green London Assembly member Darren Johnson and union leader Billy Hayes has raised some eyebrows as a result.
Mr Cable insisted that he feels "very comfortable in the Cabinet and the coalition", however.
"The coalition was formed to deal with a particular set of problems," he said.
"We have a crisis, it's ongoing. I've been very much part of [the coalition] and I'll remain so."
He insisted the Cabinet worked in a "professional, businesslike way" and denied any link between his decision to appear at the event and the wider political situation.
"My motives for being here are not at all ideological," he added.
"It's to do with my belief in reforming the voting system."
The business secretary acknowledged that he was often the focus of unwanted attention, however, as he answered a question about the alternative vote making MPs work harder than they already do.
"I do fight for individual constituents," he said, adding: "It occasionally gets me into trouble."
Last December a journalist posing as a constituent recorded the business secretary mulling the "nuclear option" of resignation against the government and declaring "war" against Rupert Murdoch's media empire. He was stripped of his media competition responsibilities as a result.