The Conservatives must "reclaim" the red, white and blue of the union jack from the far right, Liam Fox said.
Tory co-chairman Liam Fox unveils the party's conference set
"We will never surrender the colours of our flag to those on the dangerous fringe of British politics," the party co-chairman told its annual conference.
Dr Fox said the Tories were "the party of all Britain and all Britons" and would end Labour's "intruder state".
Shadow chancellor Oliver Letwin meanwhile said he hopes to be able to cut "unfair" taxes.
Outlining the party's programme for what he said would be its last conference in opposition, Dr Fox said people were sick of Tony Blair and his "soundbite" politics.
"Britain is crying out for a new direction and this week will give it," Dr Fox told delegates.
"People are fed up with talk. They want action. They don't want vague promises. They want to know exactly what a Conservative government would do - and when."
Dr Fox was seeking to rally representatives after a poor showing in the Hartlepool by-election - when they were beaten by the UK Independence Party - and in recent opinion polls.
The slogan for the week in Bournemouth is "Timetable for Action" - with the party saying it will lay out specific plans and specific timings for what they would do if elected.
Mr Letwin says the Tories will not make specific tax cut proposals until next year, when it had a clearer idea of the state of the country's finances.
This was because all political parties had too often gone back on their word in the past, and the Conservatives wanted to restore trust in politicians, he told BBC Radio 4's Today programme.
Although he cannot yet make any specific promises on tax, Mr Letwin argues the public needs to be convinced the Tories could save money by cutting bureaucracy.
A review of half of Whitehall departments had already produced £15bn in possible savings, he said.
Civil service recruitment would be frozen and sales of government assets used to pay redundancy costs without affecting frontline.
Mr Letwin pointed to "unfair" taxes such as a pensioner having to pay a third of her disposable income on council tax and a first time buyer paying £600 in stamp duty on a £60,000 house.
Taxes on savings and national insurance thresholds are expected to be other devices under attack.
He added: "When we know what the economic inheritance is, when we have done all our work on thinking down fat government, just before the election... then we can make specific commitments that we know we can deliver in my first budget.
"We won't make what we don't know we can deliver."
In his keynote speech in Bournemouth, Mr Letwin said: "Thinning down fat government is not merely an option but a moral necessity for the next Conservative government.
"It is the route to making Britain's tax system simpler and fairer."