He had vowed to return since his release in April, acknowledging uncertainty about whether he might be imprisoned again.
Poczobut, a member of Poland's Union of Poles in Belarus, crossed on Tuesday via the Bobrowniki border crossing, sources close to Polish authorities have confirmed.
He was freed in April after serving nearly three years of an eight-year sentence in a Belarusian penal colony, having been convicted of "inciting hatred" and "calling for actions harmful to national security."
Human rights organisations considered him a political prisoner, and Polish authorities had long called the case politically motivated, repeatedly raising it with Minsk.
His release came as part of a prisoner exchange between Belarus and Poland, brokered through diplomatic efforts involving the US, Moldova and Romania, amid a broader thaw in relations between Minsk and Washington.
Poczobut had said he intended to return in time for a congress of the Union of Poles, originally planned for mid-September.
Last Saturday, the organisation's leadership decided to postpone the event by six months, to March 2027, citing security concerns — the group has not been legally recognised by the Alexander Lukashenko government since 2005.
Despite the delay, Poczobut said he would still travel to Belarus this week, telling reporters in Białystok, eastern Poland, that the cause was not personal but one to which he had dedicated much of his life, adding that he wanted the association to keep functioning and growing.
Since his release, the activist has spoken publicly about his time behind bars, describing prolonged isolation and psychological pressure, and saying political prisoners are treated worse than ordinary criminals.
In November 2025, President Karol Nawrocki awarded him the Order of the White Eagle, Poland's highest state honour.
According to daily Gazeta Wyborcza, Poczobut plans to stay in Belarus for a week before travelling to the US and Canada to meet politicians and members of the Polish diaspora, and then return to Poland.
The Polish minority in Belarus is estimated at some 300,000 people, with the majority living in the country's north-western regions.
(ał)
Source: PAP