"As far as Tony Abbott is concerned, yes he was, is and will always be a good friend of mine but the party room made a decision and I accept that decision," Mr Howard said. Former prime minister John Howard with Malcolm Turnbull. Credit:Alex Ellinghausen "I encourage all Liberals, particularly people who were especially attached to Tony Abbott to... out of respect for his own wishes, to vote for the Turnbull Coalition." Mr Howard said he respected Mr Turnbull and held no grudges over their previous battles, including from the Republic debate of the 1990s. He said Mr Turnbull was better placed to lead the country than Mr Shorten. "I know Malcolm Turnbull well, I've known him for a long time, on a friendship basis not as close as I was to Tony, but there was never any real hostility between us.

"We get on very well. I think he's highly capable and he's clearly the better person able to guide this country through very difficult economic times." Former prime ministers John Howard with Tony Abbott have joined the '"no" campaign. Credit:Alex Ellinghausen He noted Australians had become "less tribal" in their voting habits. "That process of de-tribalisation, if I can put it that way, started quite a long time ago. It probably began in the early 90s, after the end of the Cold War as some of the ideology started to ebb away from politics around the world. "It has been accelerated and it's a world-wide phenomenon. You see it in the United States, you see it in Britain, you see it in other countries.

Mr Howard said the changes meant the proportion of "rock solid" voters for the major parties was lower. "There are fewer of those rusted on people. There are still a lot, I don't want to overstate it, but there are more people who float around in the middle and will think of voting in a different way perhaps several times between elections." Mr Howard also criticised independent senator Nick Xenophon for his opposition to free trade agreements, likening the position to serial candidate Pauline Hanson's views. "There are a lot of people who are normally of the conservative disposition in either Labor or Liberal who are attracted to an anti-gambling stance but he's gone far beyond that now," he said. "He's representing himself as having an attitude on everything. When you're in that position you've really got to declare yourself.