"It's been kind of on its way out in the last couple of months," Lambert allegedly said of his relationship with the Finnish entertainer and winner of Finland's 2007 Big Brother edition.
"Sauli and I remain really good friends, and I know it's a cliche thing to say, but it's totally true. I just gave him a coffee and bagel earlier today. He's a great person and we've had an amazing couple of years together. Things have just run their course."
Both parties have been dedicated to their own careers in recent months, which apparently got the ball rolling on their split.
"I've been getting really busy and traveling a lot and he's been getting really busy because he has a show he's filming for Finnish television," Lambert added, according to Us. "So we just decided to part ways."
Lambert and Koskinen were both arrested and jailed in Finland in December 2011 after getting into a fight with one another outside a gay bar. They were released from jail that same day after questioning, The Hollywood Reporter reported at the time.
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