More than 600 unaccompanied children have tried to seek asylum in the UK in the past three months, officials have revealed.

Social services in Kent say that they struggling to cope with the sudden increase in numbers, which are “rising day by day, week by week”, according to council leader Paul Carter.

The number of young migrants in the local authority's care has almost doubled to 605 in the last three months, leaving it with a multi-million pound funding gap.

Mr Carter says the council now faces a £5.5m shortfall in funds to care for this children.

Migrants gather near the Eurotunnel terminal in Calais (Rob Stothard/Getty Images)

He said: “Local government has statutory duties to provide care for unaccompanied minors under the age of 18 and those numbers have escalated dramatically in the last four to five weeks.

“That is connected with more migrants getting onto trains and in some cases boats and presenting at Folkestone or Dover seeking asylum. If they are under 18 we have to care and provide for them."

Mr Carter said he could not remember a time when a higher number of child asylum seekers arrive in Kent.

He said: "Now the numbers have escalated to these very significant levels, we are really struggling to be able to support these vulnerable young people.

"[We] have asked the Home Office and the Department for Education for additional support, with the potential to have a national dispersal system or a voluntary dispersal system with other authorities around the country, because our social services, frontline social workers, are working flat-out supporting this increase in number."

Bernie Gibson, the managing director of Compass Fostering, told the BBC Radio 4 Today programme: “We have been working with young people that have come from areas like Morocco, Eritrea. We have seen cases of these young people taking long journeys, taking lengthy crossings and coming under lorries as a result of traumatic experiences in their country of origin.

“The challenge to find foster carers nationally for Compass is challenging anyway but imagine on top of that these children are very traumatised, they don't speak English. Often they come from different cultural experiences.”

In pictures: Calais crisis intensifies Show all 20 1 /20 In pictures: Calais crisis intensifies In pictures: Calais crisis intensifies Calais crisis French gendarmes try to stop migrants on the Eurotunnel site in Coquelles near Calais In pictures: Calais crisis intensifies Calais crisis French gendarmes try to stop migrants on the Eurotunnel site in Coquelles near Calais Getty Images In pictures: Calais crisis intensifies Calais crisis A migrant climbs a security fence of a Eurotunnel terminal in Coquelles near Calais In pictures: Calais crisis intensifies Calais crisis A migrant climbs a security fence of a Eurotunnel terminal in Coquelles near Calais In pictures: Calais crisis intensifies Calais crisis French gendarmes block migrants along a road to prevent them access to train tracks which lead to the Channel Tunnel in Frethun, near Calais In pictures: Calais crisis intensifies Calais crisis Policemen try to prevent migrants from reaching the Channel Tunnel operated by Eurotunnel in Coquelles near Calais In pictures: Calais crisis intensifies Calais crisis A policeman faces migrants trying to reach the Channel Tunnel operated by Eurotunnel in Coquelles near Calais In pictures: Calais crisis intensifies Calais crisis A policeman tries to stop migrants on the Eurotunnel site in Coquelles near Calais In pictures: Calais crisis intensifies Calais crisis Migrants who managed to pass the police block on the Eurotunnel site climb over a fence to make their way towards the boarding docks in Coquelles near Calais In pictures: Calais crisis intensifies Calais crisis Migrants are seen near a Channel Tunnel train in Coquelles near Calais In pictures: Calais crisis intensifies Calais crisis Migrants trying to reach the Channel Tunnel run past policemen in Coquelles near Calaisa In pictures: Calais crisis intensifies Calais crisis Migrants step over the fence as they try to catch a train to reach England, in Calais In pictures: Calais crisis intensifies Calais crisis A migrant climbs a security fence of a Eurotunnel terminal in Coquelles near Calais In pictures: Calais crisis intensifies Calais crisis Migrants warm themselves with a fire as they attempt to access the Channel Tunnel, in Calais In pictures: Calais crisis intensifies Calais crisis An Afghan flag flies above makeshift shelters at a site dubbed the "new jungle", where migrants trying to cross the Channel to reach Britain have camped out around the northern French port of Calais In pictures: Calais crisis intensifies Calais crisis Migrants build a makeshift shelter around the northern French port of Calais In pictures: Calais crisis intensifies Calais crisis Migrants build a makeshift shelter In pictures: Calais crisis intensifies Calais crisis Migrants walk in a makeshift camp in Calais In pictures: Calais crisis intensifies Calais crisis A driver climbs on his truck as he waits to cross the English channel, in Calais In pictures: Calais crisis intensifies Calais crisis Migrants walk along the roadside while a French policeman secures the area as lorries queue in Calais

It comes as the Ministry of Defence is believed to be in the early stages of a plan to use empty land owned by the department near Folkestone to free up space on the M20.