The Taliban called off a meeting with the Pakistan Prime Minister Imran Khan on Monday, saying a UN blacklist prevented their members from travelling. News that the meeting had been planned angered some Afghan politicians who accused Islamabad of supporting the insurgents. Kabul sent a letter to the UN Security Council late last week complaining about Pakistan, calling the planned Taliban meeting a "violation of the national sovereignty of Afghanistan".<br/> "This initiative is a source of deep regret and concern to the people and government of Afghanistan as it amounts to the official recognition and legitimisation of an armed group that poses a serious threat to [the] security and stability of Afghanistan," the letter, signed by Afghanistan's Deputy Permanent Representative to the UN Nazifullah Salarzai, read. Mr Salarzai confirmed the content and authenticity of the letter, but declined to elaborate when contacted by <em>The National</em>. This is not the first such complaint. The Afghan government also submitted a letter to the UN when a delegation of senior Taliban officials travelled to Moscow last month to meet opposition Afghan figures, and previously when a delegation visited the UAE to meet US and regional figures. Such meetings are “a clear violation of the sovereignty of the Islamic Republic of Afghanistan, which is a red line for us,” foreign ministry spokesman Sibghat Ahmadi said. In a meeting with the US special envoy, Zalmay Khalilzad, on Monday, Afghan President Ashraf Ghani urged the Taliban and Pakistan to be open about their relationship. “The Taliban should clarify their ties with Pakistan, terrorist groups and the criminal economy,” Mr Ghani said. Although it is unclear if the protest by Kabul led to the cancellation of the meeting, the Taliban – which calls itself an Islamic Emirate – issued a statement blaming its inability to travel due to the UN restrictions. But many Afghans pointed out the fact that a UN blacklist did not prevent them from travelling to Moscow, Abu Dhabi or Doha where they have met US officials several times. Others also questioned the claim but said that areas of neighbouring Pakistan have, in the past, been safe havens for the group.<br/> Qatar is the base for the Taliban's political office and where many of the group's senior leaders live. “The Taliban make it sound as if they were going to fly from another planet [going] to Islamabad and because of UN blacklist, their travel was prevented. [But] their trip is just a rickshaw ride away,” former parliamentary candidate Atta Nasib said.