Pratt and the 29-year-old writer started dating a year after his split from former wife, actor Anna Faris in August 2017.
Just a day prior, United States news media reported that Chris helped Katherine move out of her Santa Monica, California home.
Eyeing 2020, Harris addresses prosecutorial past in memoir
Former US President Barack Obama described her as trailblazer. A wall along the US-Mexico border was one of Mr. Harris is the first Indian-origin US Senator.
The Parks and Recreation actor has been showered in congratulations, though some fans of the hunky monkey were a little devastated by the news.
Last December, on Schwarzenegger's birthday, Pratt captioned a tribute post: "Happy Birthday Chief!" The couple were married in 2009 and had son, Jack, in 2012. I've cherished our time together.
They have also met each other's families, and it is believed that Schwarzenegger's mother, Maria Shriver, played cupid to get them together.
Hollywood star Chris Pratt is to marry again.