Arsenal are ready to take a £10m gamble on future of Walcott

Arsenal are prepared to take a £10m hit by keeping Theo Walcott, pictured, until the end of the season if he refuses to sign a new contract before January.

Speaking after his side's 5-2 victory over Tottenham Hotspur in Saturday's typically eventful north London derby, their manager Arsène Wenger confirmed for the first time that the club will not attempt to cash in during the winter transfer window. A terse exchange with reporters went: "Will you sell him in January if there is no agreement?" "No." "So he will stay until the end of the season regardless?" "Yes."

Asked if there had been any progress on a more acceptable contract, Wenger replied good-humouredly: "If I listen to you, then every day it gets more expensive. We continue in a positive way. I told you many times we have until the end of December to sort this out."

If that does not happen, he insisted, the England international will remain for the rest of a season in which Arsenal need to make sure of a Champions League place, continue their progress in this season's competition – they could have qualified for the knockout stage by Wednesday night after playing at home to Montpellier – and pursue a first trophy for what will be eight years.

Saturday's contribution included seeing off a bemused Tottenham left-back in Kyle Naughton, who was substituted at half-time, crossing for Per Mertesacker to head the equaliser, having a hand in Santi Cazorla's goal and claiming a richly deserved one of his own right at the end to remain Arsenal's leading scorer this season.