He is due to dine with Merkel ahead of an EU-Africa summit on Wednesday

Tusk said he could understand Berlin's hesitancy for 'historical reasons'

EU's Donald Tusk warns that Angela Merkel and Germany must toughen up

The EU has issued a stark warning to Germany - it must toughen up its stance on migrants and do more to help secure Europe.

European Council President Donald Tusk has praised Berlin's leadership amid the crisis, but reiterated it must shed its Second World War past and help secure the bloc's external borders.

'Leadership responsibility also means securing Europe's external borders together with other member states,' Tusk told Die Welt am Sonntag newspaper.

Donald Tusk, a former Polish prime minister, has said Germany must toughen up its stance on the current migrant crisis

A group of migrants walk past a police sign on their way to catch a bus to Serbia from Macedonia

Families wander along a dusty road between Greece and Macedonia as the make their way to Europe via the Balkans

'I understand why due to historical reasons, Germany may have difficulty setting up a strict regime on its borders.

'But for Germany, European leadership responsibility also means controlling Europe's external borders, if necessary energetically, in a pan-European unit.'

Tusk, a former Polish prime minister, has repeatedly stressed the urgency of tightening Europe's borders, while Merkel has pushed for states to show 'solidarity' and share responsibilities for refugees.

In October, Tusk rebuked fellow European leaders by calling arguments over how to accommodate refugees 'naive' as long as Europe fails to stop them surging over its borders.

Tusk is due to dine with Merkel in Berlin ahead of an EU-Africa summit in Malta on Wednesday and EU leaders meeting on refugees on Thursday.

Meanwhile, after months without a breakthrough, David Cameron will finally give more details on tomorrow of what reforms he wants for Britain to stay in the EU before a looming referendum.

A group of migrants aboard a raft land on the Greek island of Lesbos after fleeing via Turkey

More than 130 men and women are detained on the HMS Richmond after they were found crammed into an oversized dinghy in the Mediterranean at the weekend

Nearly three years after promising a vote before the end of 2017, the British prime minister will deliver his shopping list in a letter to Tusk, which is expected to be made public.

The letter comes ahead of a crunch European summit in Brussels next month and amid hopes that the British referendum on whether to remain an EU member state can be held next year.

Cameron will warn in a speech that if Britain's concerns are met with a 'deaf ear', he will have to 'think again about whether this European Union is right for us'.