The blacklisting of al-Nusra, a group fighting Assad, by the United Nations, European Union, and United States is just for public consumption.
The US and the EU are supplying al-Nusra and other transnational terrorist groups in Syria with weapons under the table. They mistakenly believe that publicly labeling their own transnational terrorist groups as terrorists erases their connections to them in the public imagination and puts to bed the "conspiracy theories" that link them with these groups.
But, their ties to them have not been cut. So, publicly designating al-Nusra as a terrorist organization means nothing if the transfer of weapons and money is not stopped. Actions speak louder than words, even if those actions are covert.
People in Syria and around the world have eyes. They are not blind. They can see that these terrorist groups are being armed and funded by the exact same people who then turn around and act like they never met them before in their lives. It's a trick that has outlived its effectiveness.
United Nations blacklists Syria's al Nusra Front. Source: Al Jazeera.