No details were given on the new deal, which follows Mignolet's arrival at Anfield in 2013.The 27-year-old Belgium international, who is expected to join his country's squad for this year's European Championship, has made 122 appearances since then - missing just three league games.
The contract extension comes a week after Mignolet was criticized by fans and the media for his performance in a 3-3 home draw against league leader Arsenal.
"I know signing a new contract comes with new responsibility," Mignolet told the club's website. "I'm getting older as well and coming into the years where people would say those are the years a 'keeper is at his best."
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