The 23-year-old is now expected to travel to Merseyside to undergo a medical and discuss personal terms ahead of an estimated £8.5 million move.
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"He played in the youth academy of Feyenoord and made his debut under Bert van Marwijk in December 2007 against Heracles Almelo (6-0 win). In the summer of 2011 he could choose between signing a new contract or leave for FC Twente.
"He left for €5.5 million [£4.8m] and signed a contract until 2014, with an option for another season. This season he was very important for Twente, but he injured his knee and was out for two months. He's a typical box-to-box player. He's very strong in duels and scores a lot. In Holland, Fer is seen as a huge player for the future."
The signing will represent David Moyes' first foray into the market this January and comes on the back of watching Kevin Mirallas again succumb to injury in the 2-1 FA Cup win at Bolton.
Moyes hinted at an imminent deal on Monday, telling reporters: “If I have to have a bet on whether we will get someone in, then I would back myself to do it.
"When I took the job 500 games ago, I knew the situation wasn't going to be having lots and lots of cash to spend.
"I will tell the chairman what we need and hope we can do it together. I know he gives me every penny. We are pretty straightforward at the club, if you don't have money you can't spend it."
Fer has netted 11 goals in 38 games since moving to Twente, managed by Steve McClaren, in 2011.
He is a product of the Feyenoord youth academy where he spent four years as a professional, accumulating over 100 appearances for the Eredivisie side.
The central midfielder has also represented the Netherlands twice.