The 36-year-old priest, who served in the central city of Santiago on the Caribbean island and is identified only as Wojciech G for legal reasons, will be formally questioned and charged tomorrow, said Dariusz Nowak, a spokesman for prosecutors in Warsaw.
"We received documents from the Dominican Republic that, among other things, will allow us to press charges," Nowak told reporters.
Wojciech G flatly denied any wrongdoing in an October 2013 interview with Polish media, suggesting he was set up by local drug gangs.
Authorities there also suspect Wesolowski of having sex with boys. Pope Francis suspended him from his duties as papal nuncio and summoned him to the Vatican in August of last year.
Also Read
Nowak said today that "all documents from the Dominican Republic were transferred to the Vatican", though Polish prosecutors continue to investigate the case.
Unlike in the United States or Ireland, child sex abuse by priests in Poland remained a largely taboo subject until its influential Catholic Church was hit with a string of child sex allegations in 2013.
After public outcry, the country's top Catholic cleric Archbishop Jozef Michalik apologised in October for his remarks.
The church in Poland faced its first civil lawsuit for damages this month.
The demand for 47,500 euros ($63,500) was made by a 25-year-old male -- identified only as Marcin K -- who was molested as a child.
A Catholic priest was sentenced in 2012 to two years behind bars in the case, but his diocese refused to be held financially liable.