Emirates club make Reebok Stadium star third summer defensive signing.
Arsenal have agreed a £14million fee with Bolton Wanderers for defender Gary Cahill.
The 25-year-old will now undergo a medical and discuss personal terms with the Gunners.
The England international has been on manager Arsene Wenger’s wanted list all summer and last week had £6million plus add-ons bid rejected by the Trotters.
But the clubs have agreed on a basic £10million fee, which could rise £4milllion, depending on Cahill’s success at the Emirates.
He had a release cluase in his contract for £17million but with only one-year remaining on the deal, Arsenal managed to persuade Bolton to sell for cheaper.
Cahill could now become Arsenal’s third defensive signing of the day following the acquisitions of Andre Santos and Per Mertesacker.
Santos, 28, has agreed a £6.2million move from Fenerbahce and will replace Gael Clichy in competing for the left-back position with Kieron Gibbs.
Mertesacker, 26, will complete his £6million from Werder Bremen once he arrives in London this afternoon for his medical.
Germany manager Joachim Low allowed the defender to leave the national squad to finalise personal terms.
Cahill and Mertesacker will now compete with each other along with Laurent Koscielny and Johan Djourou to play alongside first-choice Thomas Vermaelen.