The decision has been made on the grounds that there are no circumstances in which it is safer to smoke than to use NRT, the MHRA said.
The extended indication for 'harm reduction' includes the use of NRT in smokers who are unwilling or unable to give up smoking completely, for an unlimited period of time.
At present, the revised indication only applies to the Nicorette Inhalator, but it is understood that more products are expected to apply to have their indications extended this year.
The change in indication reflects a move towards the use of medicinal nicotine to minimise harm from tobacco smoke.
'Nicotine is a strongly addictive substance and stopping smoking results in cravings and withdrawal effects, but it is tobacco smoke that produces the diseases and premature deaths associated with smoking,' the MHRA said.
'Providing smokers with access to less harmful forms of nicotine could benefit both them and others who would be exposed to their second-hand smoke.'
The MHRA has launched further consultation on the regulation of a range of other nicotine products, including electronic cigarettes and nicotine gels, all of which are currently unlicensed.