Mignolet will now jet back to his homeland before reporting for training at Melwood at the start of July.
On being the first Belgian to sign for Liverpool, he added: "I've been told that and it's quite a surprise to me because you see how many Belgians are playing in the Premier League today.
"It's something to be proud of - the first Belgian to play for a big club such as Liverpool.
"It's a big club and when you arrive it's a big thing. I'm very pleased to be here and I'm looking forward to getting started. The first training [session] will be very early and I'll be happy to be there.
"I tried to keep this as quiet as I could because there are a lot of things that have to be finalised before you sign. I kept it quiet because I know my friends and family, they'd get excited. But they're happy and hopefully they can come over for a lot of the games. I think they will be proud.