Inter confirmed the capture of Santon on an initial loan deal, with an option to make the deal permanent, on deadline day on Monday.
The transfer came after Santon's girlfriend claimed via Twitter that Newcastle left the 24-year-old with no other option but to leave for Inter.
There were also rumours that Santon had initially rejected Inter's offer but he used social media to clear the air.
"There has been a bit of confusion over the last few hours with people saying I first rejected Inter's offer, then was forced to come here by Newcastle," Santon wrote on Facebook.
"None of that is true. I never turned down Inter. As the negotiations all happened on deadline day, I just asked for a couple of hours to talk about it with my family and see what they thought...
"After talking to my girlfriend and my parents, all together we decided it would be a fantastic choice and therefore here I am ready to begin with my new number 21 jersey."
Santon struggled for regular game time at Newcastle following his arrival from Inter in 2011, making 82 Premier League appearances.
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