Mrs May had a meeting with the prince on the first day of the G20 summit of world leaders in Buenos Aires, Argentina.
Bin Salman told Macron not to worry, but Macron replied, "I am anxious". For the prince, it's about the killing of a dissident Saudi journalist in the country's Istanbul consulate.
Macron, undeterred and continuing on with the conversation, later says, "I'm a man of my word".
The meeting between the two leaders comes a few months after it was announced that - following US's reimposition of sanctions against Iran - India will cut its oil imports from Tehran to zero. But with the agency not publicly stating so, Trump has attempted to deflect blame away from the crown prince.More news: 'Russian Aggression' Heightens Tensions as Russia Seizes Ukrainian Ships
Saudi Arabia dismisses any suggestion that MBS had knowledge of the operation to kill Khashoggi, but Turkey has consistently hinted at high level Saudi involvement, stopping short of accusing any senior Saudi royal.
Mr Putin's spokesman Dmitry Peskov reportedly greeted news of the cancellation by saying that while it was regrettable, it left the Russian president with a couple of extra hours to meet other leaders on the sidelines of the summit.
In contrast, Mr Putin and the crown prince shared a smiley, enthusiastic greeting at the gathering.More news: PM Narendra Modi Says Congress in Power During Mumbai Attacks
Trump, in an exclamation point-heavy statement before the summit, said it did not matter whether Prince Mohammed knew about Khashoggi's death and that Saudi Arabia was important for business and for its hostility to Iran.
"We suggest renaming the street address of the Saudi Embassy into Jamal Khashoggi Way to be a daily reminder to Saudi officials" that such killings are "totally unacceptable and as an expression of Washington's unstinting support for freedom of the press", the petition states.
Mr Trump's key agenda item though, will be Saturday's dinner with Chinese President Xi Jinping - a head to head that world markets will also be watching closely.
Trump canceled his meeting with Putin on Thursday, citing clashes with Russian and Ukrainian military vessels.More news: Melania Trump uses Christmas decorations to promote 'Be Best' campaign