'The head coach came over to me and said there had been an order from above to remove me.'
A Belarusian opposition politician said Belarus officials had told Tsimanouskaya's mother that her daughter was a spy for Western governments.
A Belarusian athlete who took refuge in the Polish embassy in Tokyo on Monday, a day after refusing her team's orders to board a flight home from the Olympic Games, has been granted a humanitarian visa by the Warsaw government.
Sprinter Krystsina Tsimanouskaya plans to leave for Poland in the coming days, a Polish deputy foreign minister, Marcin Przydacz, told Reuters. She is "safe and in good condition" after walking into the embassy on Monday morning, he said.
Another deputy foreign minister, Pawel Jablonski, said: "I can confirm that we have issued a humanitarian visa. I can confirm that we will provide all necessary support in Poland if she wishes to use it."
Tsimanouskaya, 24, had been due to compete in the women's 200 metre heats on Monday but said that on Sunday she was taken to the airport to board a Turkish Airlines flight.
She refused, telling Reuters: "I will not return to Belarus."
The European Union welcomed Poland's decision and said the repatriation attempt was further evidence of "brutal repression" by Belarusian President Alexander Lukashenko.
"We express our full solidarity to Krystsina Tsimanouskaya and commend the (EU) member states that offered her support," EU spokeswoman Nabila Massrali said.
The incident has focussed attention on Belarus, where police have cracked down on dissent following a wave of protests triggered by an election last year which the opposition says was rigged to keep Lukashenko in power.
The athlete arrived at the Polish embassy in an unmarked silver van about 5 pm local time (0800 GMT). She stepped out with her official team luggage, and greeted two officials before going inside.
Two women, one carrying the red and white flag seen as the symbol of opposition in Belarus, came to the gates to support her.
Her husband, Arseni Zhdanevich, will join her in Poland, a Warsaw-based Belarusian opposition politician said.
"Thanks to the support of the Belarusian Athletes' Solidarity Foundation, (Tsimanouskaya's) husband is in Kyiv and he will join Krystsina," Pavel Latushko told Reuters.
Zhdanevich had already entered Ukraine, a Ukrainian interior ministry source said.
A Belarusian opposition politician said Belarus officials had told Tsimanouskaya's mother that her daughter was a spy for Western governments.
Pavel Latushko, who lives in Warsaw, told Reuters Tsimanouskaya had told him via text message that her mother had been approached by someone from Lukashenko's office and asked to persuade the athlete to come home.
Tsimanouskaya told a Reuters reporter via Telegram that the Belarusian head coach had turned up at her room on Sunday at the athletes' village and told her she had to leave.
"The head coach came over to me and said there had been an order from above to remove me," she wrote in the message. "At 5 (pm) they came my room and told me to pack and they took me to the airport."
But she refused to board and sought the protection of Japanese police.
Tsimanouskaya said she had been removed from the team as she had spoken out about what she described as the negligence of their coaches.
She had complained on Instagram that she was entered in the 4x400 m relay after some team members were found to be ineligible to compete at the Olympics because they had not undergone sufficient doping tests.
"And the coach added me to the relay without my knowledge," Tsimanouskaya said.
The Belarusian Olympic Committee said coaches had decided to withdraw Tsimanouskaya from the Games on doctors' advice about her "emotional, psychological state".
Belarus athletics head coach Yuri Moisevich told state television he "could see there was something wrong with her ... She either secluded herself or didn't want to talk".
Earlier on Monday, International Olympic Committee spokesperson Mark Adams said officials would continue conversations with Tsimanouskaya and had asked for a full report from the Belarus Olympic committee.
The Japanese government said she had been kept safe while Tokyo 2020 organisers and the IOC checked her intentions.
The United States ambassador to Belarus, Julie Fisher, said Lukashenko's government had tried to discredit and humiliate Tsimanouskaya for expressing her views, and she praised the Japanese and Polish authorities for their quick action.
The IOC spokesperson also said it had taken a number of actions against Belarus' Olympic Committee following nationwide protests in the country.
In March, the IOC refused to recognise the election of Lukashenko's son Viktor as head of the country's Olympic Committee. Both father and son were banned from attending the Games in December.
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