In early October, Israel's foreign minister, Israel Katz, announced on X he had declared the United Nations secretary-general, António Guterres, persona non grata. In other words, he had banned Guterres from setting foot in Israel.
Katz said Guterres' failure to "unequivocally condemn" Iran's recent attack on Israel was the reason he was no longer welcome. The strongly worded statement further accused the UN chief of failing to "denounce" Hamas' massacre in southern Israel on October 7 2023. He added:
A secretary-general who gives backing to terrorists, rapists and murderers from Hamas, Hezbollah, the Houthis and now Iran - the mothership of global terror - will be remembered as a stain on the history of the UN.
Security Council members expressed their support for Guterres after Katz's declaration. And Guterres' spokesperson called it "a political statement" and "just one more attack […] on UN staff" by the Israeli government.
What is the significance of Israel's declaration? And what kind of impact could it have?
What does persona non grata mean?
The Latin phrase persona non grata means "an unwelcome person". In international law, it refers to the right of states to exclude a diplomat or consular officer from their territory. This can take the form of expelling a diplomat or denying them entry.
Under international conventions, nations are not required to provide a reason for such a declaration.
Diplomats and consular staff enjoy a wide range of immunities and privileges under international law. Among other things, they cannot be subjected to any form of arrest or detention, nor can they face legal action in a criminal or civil court.
The diplomat's home nation must waive immunity for this kind of action to be taken.
The concept of persona non grata was therefore devised as a way to balance against these immunities and privileges. A nation that is aggrieved by the actions of a diplomat or consular officer can simply bar them from their territory, without even providing a reason.
Can UN officials be declared persona non grata?
There is a longstanding debate between the UN and its member states about the legality of such declarations.
The UN maintains its officials cannot be barred from member nations because they are not diplomats accredited to those countries. Rather, they are international civil servants who are accountable to a global organisation.
The UN also notes that declaring its officials persona non grata seriously interferes with the organisation's functions, as well as the powers of the UN secretary-general under the UN Charter.
Many countries, however, do not agree with the UN's position. In recent years, Ethiopia, Mali, Sudan and Armenia have all declared UN officials to be persona non grata, just to name a few.
Israel's declaration is only the second time a nation has specifically banned the UN secretary-general. The first time was in the 1950s when both the Soviet Union and the Republic of China declared the first secretary-general, Trygve Lie, persona non grata.
In 1961, the Soviet Union also said it would not recognise Secretary-General Dag Hammarskjold as an "official of the United Nations".
Power must be handled with restraint
I am researching this issue, which has not yet been widely explored. My study is looking at two main questions: whether states have the right to bar UN officials and the implications of doing this.
On the first question, I believe there are strong legal reasons to support the rights of states to kick out - or keep out - UN officials.
For one, nations have a wide scope of sovereign rights to decide who enters and leaves their territory. This is a cardinal principle of sovereignty.
If UN officials are suspected of engaging in conduct harmful to a country's national interests and security, it also has a right to defend and protect itself. One way of doing so is to expel the suspected UN official.
Lastly, there is no direct rule under international law that prohibits this kind of action.
Beyond these legal rights, however, is the important issue of what such an action means for the longer-term credibility and efficacy of the UN.
Because countries are not required to provide a reason for banning a foreign diplomat, this makes it a powerful political weapon if used against a UN official.
And banning UN officials specifically could also seriously jeopardise the organisation's work and put innocent lives at risk. This is especially true in the context of armed conflicts where the UN is called upon to provide humanitarian assistance.
For example, in 2021, Ethiopia expelled five UN humanitarian officials who were providing food, medicine, water and other life-saving items to more than 5 million people in a region that was engaged in armed conflict with the federal government. Given the expelled officials were high-ranking staff, the action disrupted the co‑ordination and provision of assistance.
And banning the secretary-general, in particular, is perhaps the strongest indicator of the breakdown of the relationship between a state and the UN.
The secretary-general is the chief international civil servant and the embodiment of the organisation. Their leadership is also critical for providing emergency relief, brokering ceasefires and promoting peace.
Declaring the secretary-general persona non grata, therefore, seriously damages his or her standing, especially in the context of an armed conflict. It's also a strong political statement against the UN more broadly, which could significantly complicate its humanitarian work.
Therefore, while countries do have the sovereign power to declare UN officials persona non grata, they need to exercise restraint in how they use this power. What such restraint should look like is an open question, but one that must be urgently addressed.