Britain is looking at whether it can 'do more' to help thousands of unaccompanied children fleeing to Europe but Justine Greening today warned the journey was a 'last resort' and millions more people need help in the region.

The International Development Secretary said Britain had been at the forefront of work to help refugees displaced by the fierce fighting in Syria but repeated the Government view it is better to help people still in the region.

David Cameron has come under growing pressure to relocate unaccompanied children in Europe to Britain - particularly those in the Balkans where the winter weather has taken a freezing turn for the worse.

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Thousands of migrants, including many children pictured today on the freezing Macedonia-Serbia border, are still travelling to get into Europe - despite freezing conditions in the Balkans

David Cameron is reportedly considering demands for Britain to take in thousands of unaccompanied children, pictured today near the Serbian village of Miratovic, who are making the journey alone

Hot soup is being provided for migrants who reach a transit centre for refugees near the northern Macedonia village of Tabanovce

Ms Greening told Sky News Britain's approached had 'evolved' and confirmed Britain was reviewing its response to what Save the Children has calculated are 3,000 children in Europe travelling without their parents.

She said: 'So we are playing our role, we are looking at whether we can do more in relation to...unaccompanied children because children have always been from day one at the heart of our response in the region.'

Ms Greening rejected accusations the Government was not doing enough to tackle the wider migration crisis.

She said: 'I thoroughly reject that. No country in Europe has done more to help Syrian refugees. The UK has been there since day one.

'Worldwide we're the second biggest bilateral donor helping refugees on the ground and our focus has very much been on meeting refugees' first choice....The refugees that I talk to want to stay close to home, they want to stay in the region that they are familiar with.'

Ms Greening said coming to Europe was a 'last resort, not a first resort' for many refugees.

Charities, led by Save the Children, have pressed the Government for months to do more for thousands of children, most from Syria and Afghanistan, many of whom have reached Europe.

Labour leader Jeremy Corbyn raised the pressure for Government action on a visit to 'The Jungle' camp in Calais.

The Observer said today an announcement from ministers was 'imminent'.

Whitehall sources downplayed the report - suggesting any change would mirror work already ongoing to bring refugees directly from refugee camps in the Middle East rather than those already in Europe.

International Development Secretary Justine Greening, pictured today on Sky News, said Britain's approach to the refugee crisis was 'evolving'

Temperatures have plunged in eastern Europe, where thousands of travelling migrants are camped.

So far, Mr Cameron has insisted the Government is right to go to refugee camps and rescue those most in need directly - announcing last year 20,000 highlighted by the United Nations would be brought to Britain by 2020.

He has argued moving people around Europe once they are already safe will only act a draw for more people.

Speaking in Calais yesterday, Mr Corbyn said: 'Along with other EU states, Britain needs to accept its share of refugees from the conflicts on Europe's borders, including the horrific civil war in Syria.

'We have to do more. As a matter of urgency, David Cameron should act to give refuge to unaccompanied refugee children now in Europe – as we did with Jewish Kindertransport children escaping from Nazi tyranny in the 1930s.

'And the government must provide the resources needed for those areas accepting refugees – including in housing and education – rather than dumping them in some of Britain's poorest communities.'

Shadow home secretary Andy Burnham today added: 'David Cameron has been found guilty of a real lack of judgement and leadership during this refugee crisis. He has been pursuing his own individual demands on EU migration while the rest of Europe has been grappling with the biggest humanitarian crisis since the Second World War. He has left Britain looking blinkered and selfish.

'Just miles from our own doorstep, there are hundreds of refugee children in makeshift French camps living alone in abhorrent conditions. Britain can, and should, be doing more to give those kids a place of safety and I believe the vast majority of people here would support it.

'As we approach Holocaust Memorial Day, the Government should act in the best traditions of our country's past.

Thousands of people are still trekking across the icy Balkans, pictured today on the Macedonia-Serbia border, in a desperate bid to reach the European Union

Refugees which reach the transit centre at Tabanovce have a brief opportunity to warm up before continuing their frozen journey

The refugees have wrapped up in whatever they could find to try and keep warm as they walk towards the EU border, today near Miratovic, Serbia

Liberal Democrat leader Tim Farron said: 'I have repeatedly called for the UK to take in 3,000 unaccompanied refugee orphans and the government must now move from 'looking' at the issue to actually rolling out a plan to offer these youngsters a home.

'Those who have made it to European shores now face cold winters, harsh conditions and are vulnerable to traffickers and those who want to exploit them.

'Every moment longer the Prime Minister takes to decide leaves a child alone, without protection and without a future.

'We must open our hearts to those in need and I will keep pressing at this for as long as it takes. We can and must help.'

Save the Children worker Valentia Bollenback, who is currently in Presevo, said last week: 'Instead of focusing on closing their borders, Europe's government should be doing more to give people fleeing war a dignified and humane reception.'

Asked by Mr Farron about unaccompanied children in the Commons in October, Mr Cameron said: 'We have taken the decision as a country to take 20,000 refugees and we think that it is better to take them from the camps instead of from inside Europe.

'I repeat today that we will achieve 1,000 refugees brought to Britain and housed, clothed and fed before Christmas.

'On his specific question about the 3,000 children and the proposal made by Save the Children, I have looked at the issue very carefully and other NGOs and experts point to the real danger of separating children from their broader families.

'That is why to date we have not taken that decision.'