Biospheres are not the object of a binding international convention or treaty but are governed by a "soft law" -- the Statutory Framework for Biosphere Reserves -- adopted by the UNESCO General Conference and which all countries are committed to apply.
The UNESCO Secretariat does not have a "police function" and it is the responsibility of each country, through its MAB National Committee or Focal Point, to ensure that the proclaimed biosphere responds to the criteria and functions properly.
For this, in most countries it is not necessary to enact special national legislation for biosphere reserves but rather to use the existing legal frameworks for nature protection and land/water management. This being said, an increasing number of countries are now giving biospheres a special legal status in order to reinforce their application.
In the case of a perceived problem, e.g. plans to construct an oil refinery within the site, the biosphere reserve status should be used as a platform for dialogue to arrive at an optimal solution. The MAB Secretariat will remind the concerned MAB National Committee/Focal Point of its responsibility in such cases.