Rangers says manager Ally McCoist has resigned, triggering a 12-month notice period.
The 52-year-old former Rangers striker has been in charge since 2011, coinciding with the club's financial meltdown.
In a statement to the London Stock Exchange, Rangers says talks will be held with McCoist to seek "an amicable solution in the best interests of the company," adding that it expects to make announcement before the end of the week.
The club says his salary "will increase significantly" to £750,000 for the year of the notice period.
Rangers are now in the second division after successive promotions.