Basketball journalist David Pick reported Porzingis would be suiting up for his home country during this year's event.
Porzingis skipped out on playing for Latvia during the 2015 EuroBasket event and last year's Olympic qualifying to prepare for the upcoming NBA season both times.
Porzingis' brother and agent, Janis, told reporters in April that Kristaps was "in a position to decide for himself on playing for the national side" and didn't need the Knicks' approval.
The relationship between Porzingis and the Knicks has been a hot topic since the end of last season. ESPN.com's Ian Begley reported in April that Porzingis skipped his exit interview with the team.
Former team president Phil Jackson was trying to trade the 22-year-old before he and the Knicks decided to part ways in June.
Prior to being drafted by the Knicks, Porzingis previously played for the Latvian national team and was named the Rising Star of the Year in 2015.
Latvia enters this year's EuroBasket tournament ranked 35th in the world by FIBA. The country is a No. 2 seed and will begin play on Sept. 1 against Serbia in Group D.