Justin Bieber, 18, and Selena Gomez, 20, may be a tween staple as far as couples go, but ever since their reported split last week, there has been rampant speculation about what might have caused the teenage catastrophe.

While Bieber has been careful not to say anything too direct about his relationship, or lack thereof, with Gomez, he did offer a brief explanation on the Open House Party radio show. "I don't know what to say," he said, stammering over his words. "I don't know what's gong on in my life. To even assess that, it doesn't make sense, 'cause I have not made any comment."

Part of what Bieber is not commenting on includes Victoria's Secret's Barbara Palvin, 19, the Hungarian model who was seen attending a presentation of Broadway's The Lion King on Thursday with Bieber, according to the New York Daily News. While Gomez, who reportedly briefly saw Bieber at her New York City hotel over the weekend, seemed openly affected by her (ex?) boyfriend's (and "Boyfriend" singer) relationship with Palvin, re-tweeting a photo of the two with the simple caption, "……", Palvin insisted in a couple of tweets that there is nothing going on between her and Bieber — "hey everyone, please calm down. he is all yours!! 🙂 please," she wrote.

Barbara Palvin, WENN

Palvin, who was also seen with Bieber at the annual Victoria's Secret Fashion Show extravaganza, later addressed the rumors again. "Last time im saying it, please calm down,” she wrote. “There is nothing going on w him. i met him and did a pic w him. wouldnt u do the same? 🙂 #friendship.”

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