The 25-year-old, who is believed to have cost the Reds in the region of £6m, has expressed his delight in signing for the Merseyside club
"This is one of the happiest days of my life," Enrique told Liverpool’s official website. "I have come to one of the biggest clubs not just in England, but in the world. I am really, really happy.
"They have won a lot of things including the Champions League. They have amazing players and I hope to win things here.
"In Spain there is a saying 'When the train comes in, you have to take it.’ This is the first time a big club has come in for me and I had to take [the opportunity]. I am really happy."
The defender who joined the Magpies from Villarreal for £6.3m four years ago.