The Reds signed Netherlands international Virgil van Dijk in a £75m deal from Premier League rivals Southampton in the January transfer window.
Liverpool FC spent a world record fee for a defender on Van Dijk to recruit what many considered to be one of the best centre-halves in England.
Van Dijk has helped to improve the Liverpool FC defence after the Reds managed to reach the Champions League final for the first time since 2007.
However, Croatia international Dejan Lovren has still been prone to mistakes alongside Van Dijk despite the Dutchman improving his centre-half partner.
Former Irish defender Cunningham warned Jurgen Klopp that another top centre-half is needed in the summer to make further progression.
“Klopp needs to know Lovren will keep repeating mistakes,” Cunningham told Irish radio station Newstalk.
“If Liverpool are going to compete for the Champions League and the Premier League title in the next few years, Klopp needs to go spend his money on a top centre-half.
“Even if it means sacrificing Lovren and Matip and throwing some money on the top to get a top centre-half to play alongside Van Dijk.”
The Merseyside outfit haven’t won the Premier League title but finished in second place in 2002, 2009 and 2014.
Klopp took over the reins from Brendan Rodgers back in October 2015 after a successful spell at Borussia Dortmund.
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