The Brazil international has been heavily linked with a move to the La Liga giants since Barcelona forward Neymar completed a world-record £198m switch to Ligue 1 side Paris Saint-Germain earlier this month.
According to reports in the British media, Liverpool have already rejected offers in the region of £80m and £90m for their South American playmaker as the Reds look to keep their prized asset.
However, Coutinho has now reportedly handed in a transfer request at the 18-time English champions as the Brazilian midfielder looks to secure a move to Camp Nou.
The 25-year-old scored 13 goals and made seven assists last season to help the Merseyside outfit to finish in the Premier League’s top four.
Former Liverpool captain Souness admitted that he believes the Reds shouldn’t hesitate to accept an offer in excess of £100m for the number 10.
“I would snap their hand off for £120m. He is a fabulous little player,” Souness told Irish radio station Newstalk.
“He is not the difference in terms of winning trophies because they’re not doing it. Coutinho ins’t like Luis Suarez, winning games single handedly.
“For £100m plus, I’d snap your hand off.”
Coutinho moved to Liverpool in an £8.5m deal from Serie A giants Inter Milan in the 2013 January transfer window.
The Reds have signed three players in the summer transfer window so far but have missed out on their top targets Naby Keita and Virgil van Dijk.
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