Roberto Mancini confident of beating Manchester United to signature of Robin van Persie

Roberto Mancini, the Manchester City manager, is privately confident that Manchester United do not pose a threat to him buying Robin van Persie, despite the growing sense that Sir Alex Ferguson will make one big move in the transfer market this summer in an attempt to prise back the Premier League title.

City have not yet tabled a bid for Van Persie, their top summer transfer target, though Mancini has no sense that United are preparing to provoke a repeat of last summer's chase for Samir Nasri by making a move of their own. The Premier League champions have felt for several weeks that they are getting close to agreeing personal terms with the Arsenal captain, who has also been shown around houses in the North-west by City.

But despite Mancini's relaxed outlook where last season's runners-up are concerned, United do have the funds for one big-money transfer this summer and Ferguson, who knows that the prospect of taking the title back off City will be vastly more difficult if they have Van Persie, may well argue the case for making the 28-year-old that signing. Though the player's age means that this would be a £20m outlay with minimal sell-on potential, a United side with Wayne Rooney operating behind Van Persie would be dangerous.

United's policy of not paying substantial sums for players who are over the age of 27 goes right back to 1997, when Henning Berg and Teddy Sheringham were the last outfield players of that age – Dimitar Berbatov aside – for whom United have paid more than £3m. But Berbatov proves there can be an exception to the rule and though United are unlikely to match the salary Rooney secured for himself in October 2010, a substantial signing-on fee could ease Van Persie's way to Old Trafford.

Arsenal, who did not move yesterday to speak to Van Persie after his declaration of intent to leave, would be far more willing to negotiate with United than with City – the club to whom Arsène Wenger has declared he would not sell another player.

If United do seek to capitalise on the situation, they may feel they can exploit the gap between Mancini – who once again wants to do early business – and his football administrator Brian Marwood, who must marry the Italian's desire with the strictures of Uefa's financial fair play regime. There is already frustration in the Mancini camp that Marwood is delaying on a formal opening bid for the Dutch striker.

Van Persie's determination to leave provoked the most outspoken attack yet on the Arsenal board by the club's second biggest shareholders, Alisher Usmanov and Farhad Moshiri, who have written to owner Stan Kroenke expressing "deep reservations" about how the American is running the club. Usmanov and Moshiri said in the letter obtained by the Associated Press that a "tight" financial regime is leading to Wenger "selling his best players and having to continue to find cheaper replacements".

Arsenal said last night that the letter, demanding a rights issue to reduce the club's debt and bring in funds, had "been received and the contents considered". But privately, the club are unmoved by this latest attack on their strategy by Usmanov and remain utterly convinced that a self-sustaining financial model is the right way ahead after 15 successive seasons in the Champions League.

Usmanov, who has been resolutely ignored by Kroenke, added: "It appears that a place in the Champions League will be the pinnacle of our achievement again next season. Unfortunately, in the future we may see this ambition lowered further."