Police are searching for a Portuguese woman who threatened a Thai taxi driver with a knife while refusing to pay fare.

Nadiya Serhivana Varshava, 31, who was born in Ukraine but holds a Portuguese passport, hired Thai cabbie Ladda Sangthong, 35, to pick her up from the Phuket Airport on April 1.

She agreed to pay extra for making several stops in Thalang and Patong, and smoking cannabis in the car.

However, when they arrived at their destination in Rawai, Nadiya reportedly walked out of the taxi and entered the hotel lobby without paying.

CCTV footage shows the Thai cabbie Ladda in a red shirt confronting Nadiya over the fare.

In response, the angry Portuguese woman entered the hotel pantry and emerged with a knife in hand, stomping over toward Ladda, who held her hands up and backed away.

Ladda then called Chalong Police Station officers to arrest the tourist.

Nadiya was taken to the station, but she reportedly managed to hail a cab in front of the building and escaped from the bungling cops.

A hotel worker named Deer said Nadiya had previously checked in at the hotel on March 24 and left on March 26.

He claimed she often asked hotel staff to pay for her taxi rides.

Meanwhile, police said they were unsure if Nadiya had already left Thailand.

A Chalong Police spokesman said: 'The suspect has committed this kind of thing several times, and we were able to identify her immediately upon seeing her face. We are trying to track down her whereabouts.'

Thailand has seen an influx of Russians and Ukrainians seeking safety since the conflict erupted last year.

Despite concerns surrounding continued law-breaking from some of them, Thai Prime Minister Srettha Thavisin has welcomed the influx of foreign cash and even courted reviled Russian leader Vladimir Putin.

In October last year, he invited the former KGB officer to visit Thailand to strengthen ties between the two countries.