It comes after five days of violence instigated by the country's main left wing guerrilla group, the Revolutionary Armed Forces of Colombia (FARC), which followed President Alvaro Uribe's election and left more than 100 people dead.

Mr Uribe may use his popularity to push through otherwise unpopular measures

Government officials and politicians from the major parties described the measures as both necessary and inevitable.

And business groups have also expressed support for an emergency tax system which will be used to pay for thousands of extra troops and police.

Under the system, to raise much-needed cash for the Colombian Government, a 1.2% tax on the rich will be levied.

BBC correspondent Jeremy McDermott said the FARC seemed to welcome the move as, they claim, the tax will make Mr Uribe unpopular and force him out of power.

'War footing'

The so-called "state of internal commotion", as defined by Mr Uribe, permits the Colombian leader to curtail some basic civil liberties.

Mr Uribe had invoked a provision in the Colombian constitution, allowing him to suspend such liberties in the event of a threat to the security of the state.

The Colombian press has speculated that moves could include curfews in certain areas, restriction of internal travel, a ban the use of cell phones inside rebel held territory and permission for the police to search and arrest without warrants for certain crimes.

BBC correspondents said the move indicates a country effectively moving to towards a war footing after more than 30 bloody years of battle between the left-wing guerrillas and right-wing paramilitaries.

Action wanted

Although the measures seem extraordinary, after three decades of bloodshed it seems that the public is tired of government inaction and wants results.

Analysts have also observed that Mr Uribe may use his current high approval ratings - currently around 77% - to push through measures that would have proved unpopular otherwise.

Twenty people were killed and more than 60 wounded in the initial attacks following Mr Uribe's inauguration on Wednesday in which a military academy and the presidential palace itself were targeted.

The government claims the sophisticated operations the taught to the FARC by Irish guerrilla group the Irish Republican Army.

And it is feared that the rebels may strike again before the Colombian military has had the chance to gear up fully.