Prime Minister David Cameron is to return to London overnight in the wake of a third night of rioting across the capital and will chair a meeting of the Government's emergency committee Cobra later today.
Downing Street confirmed Mr Cameron would cut short his holiday in Tuscany as the situation escalated.
He will meet the Home Secretary and the acting Metropolitan police commissioner.
The Prime Minister had previously rejected calls to return to the UK, instead leaving Deputy Prime Minister Nick Clegg to hold the fort.
Mr Clegg visited affected areas in Tottenham on Monday and Home Secretary Theresa May cut short her own trip.
She described the London riots as "sheer criminality" and vowed those responsible will face justice.
Insisting there is no excuse for "looting and thuggery", she praised officers for putting themselves in harm's way to protect the public.
So far 215 people have been arrested and 25 charged in connection with the disorder, the Home Secretary said.
"These people will be brought to justice, they will be made to face the consequences of their actions and I call on all members of local communities to work with the police constructively," she added.
Her intervention follows criticism of Government ministers for apparently taking foreign holidays at the same time.
Nick Clegg visited Tottenham, north London, after coming back from his own trip.
He has defended the Government's handling of the riots in London and described the violence as "needless and opportunist".
The Deputy Prime Minister added that the trouble on Sunday night had nothing to do with the death of Mark Duggan, who was shot by police in Tottenham on Thursday.
"It is completely unacceptable and the people who have suffered are those who have lost their businesses, shopkeepers who have lost their shops, families who have lost their homes and many people who felt very frightened in their own neighbourhoods," he said.
He said the Government stood "side by side" with the victims in "utterly condemning" the rioting and looting and there was "no excuse whatsoever" for creating feelings of "insecurity".
During a visit to Tottenham High Road to survey the wreckage, Mr Clegg said the riots would leave "big scars" on the local community.
He said: "We need to start talking together to identify everything that happened so we can rebuild, not just physically but socially.
"I should stress I don't regard this as a fleeting visit. I think the Government has to engage actively at all levels and on an ongoing basis because clearly this is something that leaves big scars and we need to work together to start to heal those scars.
"I'm very much here to hear from you and your early reactions.
"Families have lost their homes. This is a very difficult time for the community but it's also a time for the community to draw together."
Attending the scene with Tottenham MP David Lammy, he heard from jeweller Steve Moore who said he lost his shop in a fire during the riots.
Mr Clegg has also dismissed claims the Government had been slow to react to the violence, adding he rejected "completely this notion that somehow this Government hasn't been functioning very effectively".
He said he spoke to the Prime Minister, Chancellor and other members of the Cabinet last night and they are all in "constant contact".
Theresa May had joined Cabinet colleagues - including David Cameron and George Osborne - in taking a holiday.
But in a clear sign that the political pressure is mounting, the Home Secretary decided to return home.
Mr Cameron has resisted pressure to cut short his family holiday in Italy and come back to the UK.
His official spokesman said: "The Government continues to function at the moment in the same way that it does throughout the rest of the year.
"The Prime Minister does have a holiday as when he goes on holiday he takes an office with him and is in constant contact with this office back here."
London Mayor Boris Johnson has become the latest to reverse his decision to stay on holiday.
Having previously said he would not cut short his vacation as he has "full confidence" in the police, Mr Johnson's spokesman said on Monday he would return Tuesday lunchtime.
In a statement the Mayor described said the scenes of violence were "utterly appalling".
"People have lost their homes, businesses and livelihoods through mindless violence," he said.
"I understand the need for urgent answers into the shooting incident that resulted in the death of a young local man, and I've sought reassurances that the IPCC are doing exactly that.
"But let's be clear - these acts of sheer criminality across London are nothing to do with this incident and must stop now."
Mrs May and Mr Clegg are the most senior members of the Government to return but it may not stop the mounting political pressure.
Labour figures have been quick out of the blocks to criticise the Government for being absent during the London riots and world economic crisis, with Lord Prescott starting the Twitter hashtag #wheresthegovernment.