Tory leader David Cameron has promised 2006 will be a year of transformation for his party - and launched an attack on Chancellor Gordon Brown.
Cameron has previously called for an end to "Punch and Judy" politics
In a series of newspaper articles, Mr Cameron said he would introduce changes based on a "clear philosophy".
And in an advert in the Sunday Telegraph, he said: "The world is changing ... so are we."
He called the chancellor "extreme", "awful" and a "creature of the past", in an interview with the Sunday Times.
Labour Party officials have dismissed the comments, saying what counts in the long run is policy substance, not presentation.
The flurry of articles follows Mr Cameron's New Year's message on Saturday, in which he said it was an exciting time to be a Tory.
In the Sunday Telegraph advert, he seemed to signal an intention to dump the Tories' "patients' passport" health policy, saying of the NHS: "We want to improve it for everyone, not help a few to opt out."
There was no commitment to tax cuts, but instead a pledge to develop policies that "help the least well-off in society, not the rich".
In an article for the Mail on Sunday, Mr Cameron promised "a year of transformation" for the Tories in 2006, taking them towards his vision of "a modern, compassionate Conservative Party".
He said the next election would see a new generation of voters born after Margaret Thatcher's departure from power, and insisted he would not be "the prisoner of an ideological past".
In the Sunday Times interview, Mr Cameron refused to rule out tax rises if times were tough.
He has previously promised to "share the proceeds of growth" under a future Tory government between tax cuts and increased investment in public services.
However, he has now made it clear that this did not amount to a promise to make tax cuts every year.
BBC political reporter Mike Sergeant said it was "not the kind of language you'd have heard from previous Tory leaders".
"For the first time Mr Cameron talks of the need to stand up to big business - his party's traditional ally," he added.
Mr Cameron's personal attack on the chancellor came despite his promise to move away from "Punch and Judy-style" confrontational politics.
In the newspaper interview he said: "Gordon Brown is the old-style thump-thump-thump and I think that's exactly what turns people off.
"I find [him] awful because it's just like listening to a speak-your-weight machine on propaganda."
Mr Cameron, 39, who entered Parliament in 2001 and has never held office, went on to describe the 54-year-old chancellor as "very much a 1980s politician" and "a creature of the past".
He also expressed a wish to face Mr Brown, who is widely considered to be the prime minister's likely successor, calling on the PM to "get on" and quit.
"This is going to be the choice people are going to make between a rather old-style 1980s approach to politics...and a new approach I have," said the Conservative leader.
"It would be good for the country, now Blair has said he's going, that he got on and left."
Labour MP Harriet Harman, an ally of the chancellor, told the Sunday Times: "David Cameron's new style of politics seems to have lasted less than a month.
"He has woken the Tories from their slumber only to walk them up a blind alley of shallow personal abuse."