NEWCASTLE UNITED are hoping the Professional Footballers' Association will successfully strike a deal with Manchester City to ensure the difficult transfer of Joey Barton reaches a positive conclusion.

There are growing fears the £5.5m deal could collapse as City refuse to meet the midfielder's demands of a £300,000 'signing on fee' clause in his existing contract at Eastlands.

The PFA's Mick McGuire has been asked to handle the mediation after Barton turned to the Union in an attempt to ensure he can finally become a Magpies player.

But even McGuire is convinced there will be a quick outcome. "We are looking for an amicable conclusion to this," said McGuire. "I have spoken to Joey, his agent Willie McKay and Alistair Mackintosh (City's chief executive) and I also intend talking to Sam Allardyce at Newcastle.

"But this is not an easy situation because City believe Joey is not entitled to the money, because it was the player who triggered to move by activating the part of his contract that says he can talk to other clubs who bid £5.5m. City believe that by doing that, he effectively asked for a transfer."

City are in the midst of a takeover battle which is in danger of breaking down, but it has been suggested the club's new potential Thai owners are trying to bide time as they want to retain the services of the controversial midfielder.

Allardyce, who thought he had landed his man nearly two weeks ago, said: "They (City) are out of order. This is a private matter, a confidential issue that should not have been made public. I'm flabbergasted and want the situation resolved.

"I'm just trying, as Newcastle manager, to secure a player of this kind and quality and the deal has been held up. I can't understand it because City didn't pay anything for this player as he came through the youth system, and they are selling him for over £5m.

"But it is not really for me to comment. All I know is that this is a matter for Joey to sort out and I hope it is resolved as it has stopped him putting pen to paper. I found Joey a very bright person who wants to develop his game."

Newcastle striker Obafemi Martins looks certain to escape punishment for his latest disappearing act after a bout of infighting caused ructions at the Nigerian Football Association.

The Magpies had been expecting to hear from Nigeria coach Berti Vogts and Super Eagles officials when the 22-year-old failed to arrive for a friendly with Kenya earlier this month.

But, since that time, Vogts has been at loggerheads with the NFA for failing to provide suitable training facilities and has blamed poor preparations for the African Nations Cup qualifier defeat to Uganda on June 2.

Martins did actually make an appearance as a second half substitute in that fixture and he has met up with the rest of the squad again ahead of this Saturday's qualifier in Niger.

Such has been the atmosphere around the Nigerian camp, former Scotland boss Vogts has threatened to walk away from his post and the whole position has meant Martins' situation has been brushed under the carpet.

There was talk prior to the Uganda game that action was going to be taken against Martins. However, that would now seem unlikely.

Newcastle's £10m striker - who could have faced an international ban - held showdown talks with Vogts recently and has been told in no uncertain terms by the former Scotland coach that any further failures to show for matches will not be tolerated.

It was not the first time he had gone AWOL, he failed to turn up for a friendly with Ghana at Brentford in February. Incidents like these hardly paint a glowing picture to Newcastle boss Sam Allardyce, who could decide to cash in on him if the right deal comes along this summer.

Just hours before Allardyce was confirmed as the new St James' Park manager, Martins refused selection for the club's final Premiership game of the season at Watford in May when he claimed to have an injury that went undetected by medical staff.

Newcastle confirmed yesterday that Nolberto Solano has signed a one-year contract and young keeper Tim Krul has penned a four-year deal