(Adds Greece aid request, paragraph 15)
* Build-up of thousands of migrants inside Greece
* Tent city pops up on closed Greece-Macedonian border
* EU prepares to offer emergency aid to Greece
* Financially strapped Greece seeks 480m euros in aid
By Stephanie Nebehay and Gabriela Baczynska
GENEVA/BRUSSELS March 1 (Reuters) - The build-up of
thousands of migrants and refugees on Greece's northern borders
is fast turning into a humanitarian disaster, the United Nations
said on Tuesday as the European Union prepared to offer more
financial aid.
German Chancellor Angela Merkel said clashes at Greece's
border with Macedonia on Monday - when migrants battered down a
gate and were tear-gassed - simply underlined the urgency with
which the EU needed to act on the crisis.
But Austria - which last month limited the number of
migrants it lets through to 3,200 a day - stuck to its position
that it did not want to become an overcrowded waiting room for
thousands wanting to make it further north.
Croatia, which is also on what is now the well-trodden
migrants route northwards from Greece, said it might deploy its
armed forces to help police control flows.
But near Idomeni, on the Greek-Macedonian border itself, a
tent city mushroomed, prompting some despair among those trapped
there. "Macedonian police put us here, the Greeks don't want us
back," Yase Qued, a 16-year-old from Afghanistan, told Reuters.
The United Nations High Commissioner for Refugees (UNHCR)
called for better planning and accommodation for at least 24,000
it said were stuck in Greece, including 8,500 at Idomeni.
"Europe is on the cusp of a largely self-induced
humanitarian crisis," U.N. refugee agency spokesman Adrian
Edwards told a news briefing.
"The crowded conditions are leading to shortages of food,
shelter, water and sanitation. As we all saw yesterday, tensions
have been building, fuelling violence and playing into the hands
of people smugglers," he said.
Migrants have become stranded in Greece since Austria and
other countries along the Balkans migration corridor imposed
restrictions on their borders, limiting the numbers able to
cross.
Police chiefs from Macedonia, Serbia, Croatia and Slovenia,
meeting in Belgrade, agreed to improve the system of joint
registration of refugees to unblock gridlocks in Greece.
The burgeoning crisis adds to last year's chaos when more
than a million migrants and refugees arrived in the EU, many
fleeing the war in Syria and walking from Turkey northwards.
Around 131,000 have reached the continent so far in 2016.
CRISIS AID
The European Commission, the EU executive, said it would
float a plan on Wednesday to offer emergency financial aid for
humanitarian crises inside the 28-nation bloc - comparable with
operations it has launched elsewhere in the world.
Officials said the Commission plan would allocate 300
million euros ($325 million) this year to helping any EU state,
not only Greece, deal with such crises, and 700 million in all
over the three years to the end of 2018.
The Greek government said it had asked the Commission for
480 million euros worth of assistance, including ambulances,
blankets and personnel to help with 100,000 asylum seekers.
Commission President Jean-Claude Juncker spoke to Greek
Prime Minister Alexis Tsipras and European Council President
Donald Tusk was on a visit to Austria, Slovenia, Croatia,
Macedonia, Greece and Turkey.
Tusk's tour comes ahead of a special European Union summit
on the crisis next Monday. Germany's Merkel said television
pictures of migrants desperate to make their way into western
Europe via the Balkans drove home the urgency of the summit.
"The pictures show us clearly every day that there is a need
for talks," she said after meeting Croatian Prime Minister
Tihomir Oreskovic in Berlin.
"We also naturally need to deal with the very difficult
situation in Greece and see how we can fulfil what the
(European) Commission demanded from us, namely to end the
politics of waving people through and to return to the Schengen
system as soon as possible and to the greatest possible extent."
The difficulty of reaching agreement on an issue which goes
to the heart of public fears for security and safety in many
countries was underlined by Austrian Chancellor Werner Faymann,
who honed in on comments from German Interior Minister Thomas de
Maiziere that suggested he thought Austria might wave through
too many migrants.
"What is not acceptable is to say that they should
definitely come and then the interior minister says he is
against waving people through (to Germany)," Faymann told a news
conference after a weekly cabinet meeting.
"Then how should they go to Germany?"
The UNHCR, meanwhile, urged all EU member states to
reinforce their capacity to register and process asylum seekers
through their national procedures as well as through an EU
relocation scheme.
"Greece cannot manage this situation alone," Edwards said.
Despite commitments to relocate 66,400 refugees from Greece,
EU member states have so far pledged just 1,539 spaces and only
325 people actually have been relocated, he added.