New York governor Andrew M. Cuomo is to legalize the use of marijuana in the state, using a decades-old public health law provision, the New York Times reports. The drug – which remains banned federally - will be prescribed for diagnosed medical ailments.

The liberalization of the previously strict local laws will be announced during Wednesday’s State of the State address, according to unnamed officials who spoke with the newspaper.

According to the proposal, twenty hospitals across New York State would prescribe marijuana to alleviate the symptoms of a list of certified conditions such as cancer, multiple sclerosis and glaucoma. The dispensaries and medical protocols have not yet been approved, but the state reportedly hopes to put the infrastructure in place within the year. Since growing marijuana plants remains illegal, it is not clear how the drug would be obtained by medical institutions, though there has been suggestion that they may acquire it from the confiscated stocks of law enforcement agencies.

If the program becomes operational, New York will become the 21st state in the US to allow at least some legal use of cannabis.

On average about 50,000 people a year are arrested in connection with the drug, the vast majority of whom were sanctioned for smoking in public in New York City, which maintains a policy of strict and visible policing. A year ago Cuomo moved to decriminalize 'open-view possession', changing the penalty from a misdemeanor to a fine, though the new laws have not come into force.

A major obstacle to any reform has been the Democrat-Republican coalition in the State Senate, which has blocked four previous bills allowing medical marijuana. Instead of taking on the legislature, the New York Times says that Cuomo has decided to revive a long-dormant provision in the state public health law allowing the use of cannabis for medicinal purposes. The 'Antonio G. Olivieri Controlled Substance Therapeutic Research Program', passed after an appeal by a dying State Assembly member back in 1980, was previously considered costly and impractical, and never implemented.

Despite polls that have consistently shown that a large majority of New Yorkers support the legalization of marijuana, Cuomo himself had previously been ambivalent on its legalization. In turn, the new dispensation program is likely to be far stricter than that in other states like California, where medical marijuana is prescribed even for trivial medical issues, meaning that those who want to use the drug recreationally have little trouble getting their hands on it.

Only two US states allow open recreational use of cannabis at present. Colorado opened its first legal marijuana retail outlets on January 1, and Washington is set to do the same later this year.

At the same time a legal rift is opening up between increasingly liberal local legislation, and federal laws, which still forbid its cultivation and possession.

Barack Obama - himself an admitted cannabis smoker in his younger years - has said that his administration will not challenge state practices, but has made no attempt to push through a nationwide legalization of the drug.