The senior business leader who stepped down after voicing his support for Brexit has insisted he "voluntarily resigned" and was not pushed.
John Longworth quit as director general of the British Chambers of Commerce (BCC) following the controversy over his suggestion the UK could have a "brighter" future outside the EU.
Number 10 has strenuously denied claims by Brexit campaigners that it put pressure on the BCC to act following Mr Longworth's comments at the group's annual conference on Thursday.
Speaking to Sky News, Mr Longworth said: "I've voluntarily resigned as director general of the British Chambers of Commerce in order to have the freedom to express myself on the European referendum."
He said he did not "know anything" about claims the BCC, which has a neutral stance on the EU referendum, may have faced political pressure to remove him from the role.
But pressed on the matter, he added: "What I can say is that Government departments, including Number 10, from my experience actually contact business representatives all the time and express their views, sometimes very strong views and strident views
"But I have to say in my experience it has never affected my position, I've always represented business views without fear or favour."
And he insisted he had not spoken to any pro-Brexit campaigners before he decided to speak out at the conference last Thursday.
He said: "I didn't speak to them about this decision at all, or anyone else for that matter. It was entirely my decision. Of course, in my role I spoke to all political parties about all issues."
Mr Longworth, who spent nearly five years at the BCC, was speaking in a personal capacity when he said Britain would be better off outside the EU.
The businessman said he was attempting to "inform the debate" on Brexit by making his comments, but admitted he was not sure he would be allowed to stay in his position after he made them.
"I wasn't certain that would be the case and I understand the BCC's decision," he said. "But I thought it was such an important matter it was important for me to speak out.
"I had no idea what the consequence would be, but I have chosen to resign from the British Chambers of Commerce because I understand their position, and while I do not think I did anything wrong, nonetheless I think it is important that I respect the British Chambers."
A number of Brexit-backers had hit out at the BCC's decision to suspend Mr Longworth over his comments, with Boris Johnson saying he had been "crushed by the agents of Project Fear".
Mr Longworth said he was "very grateful" for the Mayor of London's intervention, adding "that was extremely helpful support for me; it certainly cheered me up over the weekend".
He also revealed that while he had not spoken to Mr Johnson, he would "consider" being a spokesman for the official Leave campaign.
He said: "I am still considering what to do at the moment, but I am certainly going to speak out on the European referendum because that is the very reason why I have resigned."
His comments come as Mr Johnson told the Press Association he thinks the businessman will join the out campaign where he can "speak his mind".
Senior Tory backbencher David Davis has asked for details of Government communication with the BCC relating to Mr Longworth's suspension and resignation.
He said: "The last thing we want to see is a witch-hunt against business leaders brave and astute enough to make the argument that Britain would be better off economically if it regained the power to strike its own trade deals and was freed of the crippling burden of red tape, costing many billions a year, imposed by Brussels.
"We need a clear statement by 10 Downing Street that the Government was not involved in pressurising the BCC into suspending Mr Longworth."
But Defence Secretary Michael Fallon dismissed claims the Government had intervened to force Mr Longworth out of his job as "bizarre conspiracy theories".
He told Sky News: "The board of the British Chambers of Commerce have made it very clear that this was their decision, and there was no external pressure from anybody else."
Prime Minister David Cameron's official spokeswoman said that Number 10 has "regular discussions" with major business organisations, but declined to go into detail about any contacts since Mr Longworth's speech.
His decision to step down was "a matter for Mr Longworth and the BCC", said the spokeswoman, adding: "No pressure was applied by Number 10."