Lord Heseltine has been sacked as a government adviser after backing an amendment to Theresa May's Brexit Bill.
The former Conservative Cabinet minister told ITV News he had to "stand up and be counted" over Brexit - the "overarching issue of our time".
Lord Heseltine voted in favour of amending the legislation which was debated in the House of Lords on Tuesday.
The Tory grandee told fellow peers that the UK was facing "the most momentous peacetime decision of our time" and demanded a "meaningful" vote on the final Brexit deal.
Speaking after his sacking Lord Heseltine told the BBC Radio 4 Today programme that he knew there could be consequences if he rebelled but he was not warned that he could lose his advisory roles.
He added that he had been working for the Government part-time for the last six years but had "no relationship" with Prime Minister Theresa May.
He said he was dismissed by the chief whip in the Lords but has still not heard from Number 10.
Lord Heseltine said: "But I'm not complaining, I was getting on with the job that I was doing."
On Tuesday, peers voted 366 to 268 in favour of amending the Bill to give Parliament an opportunity to reject Mrs May's final negotiated deal with the European Union - potentially delaying Britain's departure from the bloc.
Lord Heseltine said he was forced to abandon dinner with his wife to receive his marching orders following the Brexit Bill vote.
Speaking to ITV News shortly afterwards, he said: "I voted as I said I was going and I've now been sacked - that's the prime minister's prerogative."
He said Brexit is the "overarching issue of our time" and "you need to stand up and be counted, do what you believe to be right".
Lord Heseltine added: "We have no idea what deal we'll get with Europe will be... We've no idea what British public opinion will be in two years time. In the end we have to make a judgement whether what's on offer is in Britain;s self interest. Who's to do that? My view is simple, it has in the end to be parliament."
He said he didn't expect to be sacked but "they've decided they have to make an example of me and that's entirely their prerogative."