Merkel is battling for a deal that will see refugees more evenly spread around the European Union after Germany welcomed 1.1 million asylum seekers last year, AFP reported.
But instead, eastern European countries are planning new razor wire fences, and even Paris -- traditionally Berlin's closest EU ally -- has shown little enthusiasm for Merkel's welcome policy.
French Prime Minister Manuel Valls said Saturday that the mood in France was "not favourable" to Merkel's call for a permanent quota system.
"Europe cannot take in all the migrants from Syria, Iraq or Africa," Valls told German media. "It has to regain control over its borders, over its migration or asylum policies."
US Secretary of State John Kerry praised Merkel for showing "great courage in helping so many who need so much" amid "the gravest humanitarian crisis in Europe since World War II".
But he also told the Munich Security Conference that the mass influx spells a "near existential... threat to the politics and fabric of life in Europe".
Merkel is planning to bring together what the media have dubbed a "coalition of the willing" on the margins of a two-day EU summit in Brussels starting Thursday.
She suggested its members could help Turkey's refugee effort beyond the three billion euros ($3.3 billion) already committed by the EU.
Turkey, which is hosting over 2.7 million mostly Syrian refugees, has voiced deep frustration with the EU as a fresh wave of Syrian refugees mass on its border.
Angry over calls that Turkey should do more, President Recep Tayyip Erdogan said last week that his nation could throw out its existing refugees, threatening to fly and bus them to Europe.
"We do not have the word 'idiot' written on our foreheads," he said.
"We will be patient, but we will do what we have to. Don't think that the planes and the buses are there for nothing."