"There must be no new thinking and no new ideas." This statement is not necessarily one that you might expect from an intergovernmental forum on a hot topic of international policy - except perhaps when that policy is about drugs. This statement sadly, but also neatly, encapsulates the sense of frustration that I can often feel at the UN Commission on Narcotic Drugs (CND) - the annual meeting of the UN on all matters related to drug control, which took place last month in Vienna.

A lot happens at the CND, and there were many highlights from this year's meeting - not least the strong presence and engagement of civil society and young people. But the deeply entrenched positions of certain governments when it comes to drug policy continues to stagnate the debate - aided and abetted by the CND's insistence on all decisions being made by consensus.

The statement above was made by a government official with specific reference to an important global meeting when world leaders will come together to discuss the future of drug control at the United Nations - the upcoming UN General Assembly Special Session (UNGASS) on drugs in April 2016. The same meeting that Mr Ban Ki Moon, the UN Secretary General, referred to as an opportunity "to conduct a wide-ranging and open debate that considers all options". There are a number of governments that also genuinely want an honest and meaningful discussion next April - most notably Mexico, a country that has perhaps most acutely felt the pain of the war on drugs. Some want to talk about new approaches and new options. But it is clear that they face fierce opposition from hardline, prohibitionist countries who want to limit the discussions and drown out progressive voices with UN bureaucracy and procedure.

In the rarefied air of Vienna, the official debates reflected the growing fault lines in global drug policy. The much-revered "Vienna Consensus" continues to weaken as the divide between some governments grow increasingly irreconcilable. A growing number of governments believe that current drug control leads to disastrous consequences for human rights, public health, citizen security and sustainable livelihoods, and that it has to be modernised. We heard an increasing number of national statements that stressed the primacy of human rights and for drug policy to ensure positive outcomes for public health. This includes ensuring adequate access to essential medicines such as ketamine, which avoided being placed under international drug control by a hair's breadth at this meeting (a move that would have severely limited access for its use as an an anaesthetic - often the only available for surgery - in many resource constrained settings).

However, other countries are deeply wedded to the status quo - to the extent that they reject decades of scientific evidence in order to not support harm reduction measures for people who use drugs and continue to impose the death penalty for drug offences. I am reminded of Mr Yury Fedotov, the Executive Director of the UN Office on Drugs and Crime, who last year called it "a broad consensus", when one country now allows the use and trade of certain drugs, while in another country such activities could result in the death penalty.

But in an environment of diplomatic politeness, no particular country gets called out for either taking a 'new approach' (such as cannabis regulation in the USA or Uruguay which falls outside what is permitted under the UN treaties on drug control), or for continuing to apply the death penalty, a practice that is clearly outside of countries' international human rights obligations. Instead, member states either respectfully cited international human rights instruments in their argumentation for less punitive approaches or reminded those present that strict adherence to the UN treaties is of paramount importance as they continued to defend repressive responses. It is a strange diplomatic dance that hampers progress and seems to sanction a denial of the changing tides in the real world. Yet this denial and disconnect is what risks making the whole principle of international cooperation on drugs increasingly irrelevant.

Undoubtedly the biggest challenge to the international drug control system founded on the prohibition of non-medical, non-scientific use of certain substances, is the steadily increasing trend of regulating cannabis for recreational use. Uruguay is the first country to do this at the national level and a growing number of US states now have legal cannabis markets. The cannabis social club model that started in Spain is now gaining popularity in other cities across Europe. The reform of cannabis policy has begun. It is a reality. Yet this is still not intelligently discussed at the CND, reflecting a staunch refusal to accept that any modernisation of international drug control is needed. 'If we can't agree on it, we shouldn't talk about it at all'.

This is why we have such high hopes for the UNGASS next year. The fact that it is in New York means that there will be more governments present than at CND - more voices and more experiences being shared. 4,220 miles away from Vienna, we hope that the stifling, entrenched and circular debates of CND can be left behind. The UNGASS can be a place for new thinking and new ideas.

Outside of the diplomatic bubble, the high-level questioning of the war on drugs continues unabated: former UN Secretary General Kofi Annan, concerned about the impact of drug policies in West Africa, wrote last week in Vice, "...drugs may have destroyed many people, but wrong governmental policies have destroyed many more. Let us not repeat this mistake." Similarly, President Obama has now openly admitted the dismal failure of draconian policies to curb the drug trade and cited the collateral damage that such policies have wreaked on American society - particularly among the African-American and Latino communities. He said he felt encouraged that people were talking about this issue in a "smarter" way. That is the same hope that many of us have for the UNGASS in 2016 - that it will be a smarter conversation that reflects reality rather than ideology.

Ann Fordham is the Executive Director of the International Drug Policy Consortium. Follow Ann on Twitter: www.twitter.com/@annfordham