Aleksandar Mitrovic
Aleksandar Mitrovic has made just six substitute appearances since Newcastle's return to the Premier League Michael Regan/Getty Images

Newcastle United are believed to be shopping out-of-favour striker Aleksandar Mitrovic during the January transfer window amid reports that manager Rafael Benitez has been told that he must sell before he can buy this month.

The lack of expected progress in takeover talks between current owner Mike Ashley and Amanda Staveley's PCP Capital Partners group has left Benitez still uncertain as to his budget as he desperately seeks to strengthen his limited squad for a likely relegation battle.

It was said by the Sunday Mirror that Staveley footing the bill for new arrivals was one of several scenarios put to Ashley, but that such a possibility was predicated upon the two parties agreeing a sale price.

That has obviously yet to happen, with the Sports Direct founder and majority shareholder rumoured to be holding out for £300m ($406m).

The Sun now claim that internal tensions are rising again with Benitez, who may now be forced to settle for low-cost loans amid links to the likes of Liverpool striker Danny Ings and Chelsea winger Kenedy, now locked in something of a transfer stand-off with the club as he does not want to sanction any personnel departures from St James' Park before bringing new players through the door.

That report states that the Spaniard is even refusing to sell the likes of Mitrovic, though French outlet Foot Mercato suggest that Newcastle - seeking a €12m (£10.5m) fee for a player they signed from Anderlecht for £13m in 2015 - have offered him to several European clubs including Marseille, who have dismissed the possibility despite the struggles experienced by summer signing Kostas Mitroglou.

Struggling Ligue 1 rivals Bordeaux are believed to have opened talks with the hot-headed Serbia international's camp, per RMC Sport, but are unlikely to be able to meet those aforementioned financial demands as they seek a loan agreement.

Mitrovic has made just six substitute appearances in the league to date in 2017-18, with a back injury and the birth of his child meaning he has not played since 9 December. A possible return to Anderlecht has been mooted after he declared an intention to find a club where he could play more regularly, while Partizan Belgrade and West Bromwich Albion have also been mentioned in connection with a January swoop.

Newcastle, who will face either Chelsea or Norwich City in the fourth round of the FA Cup, have risen to 13th in the Premier League table after notching up successive away wins for the first time in more than three years but remain just two points above the bottom three.

West Ham United's Manchester City loanee Joe Hart, teammate Diafra Sakho, Las Palmas midfielder Jonathan Viera, Leicester City's Islam Slimani and Real Madrid right-back Achraf Hakimi are among the other players said to be on Benitez's radar, while the likes of Henri Saivet, Freddie Woodman, Jack Colback and Jamie Sterry could all leave Tyneside before the window closes.

Jonjo Shelvey is known to feature on West Ham's shortlist of preferred midfielder targets, but it is understood that Benitez has no interest in potentially strengthening a bottom-half rival.