Over the decades, the United Nations has tackled some of the world’s biggest humanitarian crises and many say the situation in Venezuela is no different.

Washington has called for the UN Security Council to hold a special session on Venezuela on Saturday.

But for the UN, this remains a sovereign matter and, so far, it’s not taking sides.

As more nations side with Juan Guaido, Al Jazeera's Andy Gallacher explains the difficulties facing the UN.