China follows Russian admonishment of the Syrian government while the opposition Syrian National Council gains support in Egypt and is recognized by Libya.
North Korea stated that it would dismantle the Punggye-ri Nuclear Test Site between May 23–25 ahead of the Donald Trump-Kim Jong-un summit meeting. Furthermore, North Korea invited journalists from the United States, South Korea, China, Russia, and the United Kingdom to cover the process.
The Russian military launches cruise missile strikes from the Mediterranean on ISIS positions in Al-Raqqah, the Islamic State of Iraq and the Levant's de facto capital in Syria, Aleppo, and Idlib. A U.S. official confirms that Russia has conducted a significant number of strikes in Syria using both sea-launched cruise missiles and long-range bombers. Russian President Vladimir Putin has pledged to escalate his military campaign in Syria after it was confirmed that a bomb brought down Metrojet Flight 9268 over Egypt's Sinai Peninsula.
Russian ministers led by Foreign Affairs Minister Sergey Lavrov including Defense Minister Sergey Shoygu arrive in Cairo and meet with their Egyptian counterparts including the head of Egypt's military General Abdel Fattah el-Sisi in talks over a new era of enhanced military co-operation.
The UN Security Council fails to agree a statement to condemn the killing of Syrian protesters, as Russia and China block a statement proposed by Britain, France, Germany and Portugal that would have condemned the violence, which has led to hundreds of dead, and backed calls for an independent investigation.