Svetlana Z. knew it was time to flee when she noticed that planes were no longer taking off or landing at the airport near their house in the north-eastern Ukrainian town of Kharkiv.

"It was intuition. When the planes stopped flying, we knew it was the start of something bad," she told AFP, holding her two-and-a-half-year-old son close while the family of three waited for Berlin authorities to process their registration.

That fateful day - Tuesday - they packed up a few bags of essentials, and piled into their "old car" and headed westwards.

Less than 48 hours later, Russian President Vladimir Putin unleashed a full-scale invasion of Ukraine. 

"There was no accommodation in the west, in Lyiv," Svetlana said, so they kept driving, first crossing into Poland before finally arriving in Berlin on Friday.

Asked why they did not remain in Poland which is closer to home, she burst into tears, saying: "We cannot go home."

They are in constant contact with loved ones back in Ukraine, but "there is only bad news now".

Her family counts among dozens of first refugees arriving in Europe's biggest economy from Ukraine.

Germany, which in 2015 took in more than a million migrants -- many fleeing war in Syria and Iraq -- has pledged to "provide massive help" should there be a large-scale influx in neighbouring nations of Ukrainian refugees.

'Palpable bewilderment'

So far the numbers of new arrivals are small.

"We have had about 75 Ukrainians today. But we're expecting far more in the coming days," Sascha Langenbach, spokesman for Berlin city's refugee affairs office, told AFP.

"They haven't been so emotional such that we always see tears, but their bewilderment at what is happening in their homeland is almost palpable," he said. 

At the Berlin reception centre, officials had readied 1,300 beds, with capacity to be doubled in the next days. 

Staffing has also been boosted with Ukrainian or Russian speakers.

Small groups of people seeking aid were arriving, some accompanied by relatives or friends living in Berlin, others like Svetlana's family had found their way themselves.

The usual procedure is for officials to register the asylum seekers and then allocate them beds for the first few nights at the reception centre, before a more permanent home is found for them. 

But officials at the Berlin centre were advising Ukrainians who have relatives or friends in town to stay with them at least through the weekend as they expect the government to decide on a simplified asylum process for Ukrainians in the next days.

The eased procedure should allow Ukrainian asylum seekers to find work quickly, or to head directly to other parts of Germany where they may have relatives, rather than be bound to remain in the city where they first file for asylum. 

"That would make it far easier for them to find their feet here," said Langenbach, adding that his office was expecting a decision "after the weekend".

No one asked them

Tattoo artist Dmitry Chevniev, 39, was among those who have opted to hold off from registering officially pending the decision.

Chevniev had found himself stranded in the German capital.

"I arrived two weeks ago to visit friends, and now I can't go home," he said. 

His wife and their four-year-old are in Russia visiting his mother-in-law, he said, adding that he had come to the registration centre to find out what he could do to bring them over.

Stanislav Shalamai, 26, meanwhile was relieved to be given a bed for the night at the centre.

He had left Kyiv on February 15 as war had been predicted to begin around then.

"I was nervous about that so I took my stuff and left."

Carrying a dufflebag and a duvet, he took a bus from Kyiv to Warsaw before getting on another bus to Berlin.

Shalamai said he still found it hard to believe the turn of events.

"40 million Ukrainians live there, no one asked them what they want and some other army just came and started shooting at people and killing people," he said.

Shalamai said he had asked his parents to flee with him, but "they said we were born here, we lived here all our life, and we just don't want to leave."

"I don't know what is waiting for me here... I don't know what will be in Ukraine. I will have to see," Shalamai said.