How to value the cost of the land in building in chs ?

Dear Friends... 

Please Help...

A company has bought an office premises in a buillding in Co-Operative Society & has charged depreciation as per Income Tax Act. on  total cost of the Office Premises.

Department is of the view that depreciation on Land is not permissible &  Cost of  the Land in Mumbai is very high. Therfore, separate  the value of  the land as per stamp duty registration value & depreciation is allowable only on remaining cost. of the office premises.

Is the treatment done by the Company Correct ?

or

Any other View ??

Thanks