Brown won his 50th and final cap against Denmark back in March but has now decided to call time on his run in a bid to prolong his Celtic career.
Rangers are hoping to complete the capture of Joleon Lescott before the weekend after manager Mark Warburton sold an Ibrox move to the Villa defender.
Rangers' Mark Warburton sees no need to ask Joey Barton to tone down his comments after he said Celtic's Brendan Rodgers was having a mid-life crisis.
Boss Brendan Rodgers insists his Celtic side answered a big question about their mentality during a pulsating 5-2 win over Hapoel Be'er Sheva.
Australia's head coach believes manager Brendan Rodgers has helped Aussie Tom Rogic reach top form at Celtic.
Rangers have earmarked Aston Villa defender Joleon Lescott as the final piece of their summer transfer campaign.