The Gunners began pre-season on Monday with White back among the squad after recovering from the medial ligament injury he suffered during May's Premier League victory over West Ham. The setback ruled the England international out of Arsenal's run-in, the Champions League final and England's World Cup campaign.
After spending much of the summer rehabilitating at Arsenal's training ground, White confirmed he has resumed full training.
"I've been training every day, really. Knee's all good. Started training back with the team last week," he said.
The 28-year-old had already joined several teammates at a training camp in Marbella before reporting back for the official start of pre-season.
Timber is not yet back in full training but believes his return is drawing nearer after recovering from the groin injury he sustained against Everton in March. The Dutch defender missed the closing months of last season and, although he made a brief substitute appearance in the Champions League final, he was later withdrawn from the Netherlands' World Cup squad after failing to recover fully.
"Getting there slowly. Trying hard. Been rehabbing over the (English) summer, hopefully back soon," Timber said.
The availability of both defenders will be a welcome development for Arsenal as they prepare for another demanding campaign. White's return strengthens Mikel Arteta's defensive options immediately, while Timber is expected to rejoin the squad once he completes the final stages of his rehabilitation.
Arsenal open their pre-season schedule against Girona on August 1 before taking on Real Betis, Borussia Dortmund and Como. They then face Manchester City in the Community Shield on August 16 before beginning the defence of their Premier League title at home to newly promoted Coventry City on August 21.
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