Iga Swiatek will not play for Poland in next month's Billie Jean King Cup finals in Glasgow, the world No. 1 said on Monday, as she took issue with the sport's governing bodies and their handling of the tournament calendar.

Swiatek helped Poland progress to the finals in April, but the tournament will be held from Nov. 8-13, just one day after the season-ending WTA Finals which will be held in Fort Worth, Texas, this year.

"I was thinking it through a lot and discussing it with my team all over again, but I will not be able to play at the Billie Jean King Cup in Glasgow. And it makes me sad," Swiatek said on Instagram. "I'm very sorry, because I play for Poland whenever it's possible and I always give it my best. Playing in Poland this year was an honor and I hoped to do this again at the end of the season.