The UN, EU and the International Atomic Energy Agency (IAEA) last Monday called for the preservation of the Iranian nuclear deal before a May 12 deadline set by U.S. President Donald Trump.
The tree, a European sessile oak, came from the site of the Battle of Belleau Wood, which took place in the summer of 1918.
The brewing mystery has not been addressed by White House officials, while an official from Mr Macron's office said the tree had been dug up hours after it was planted and was put in quarantine. According to U.S. Customs and Border Protection guidelines, the tree needed to be quarantined before it could be permanently planted. News photos from Saturday (April 28) show a patch of discolored grass where the tree stood only a few days earlier.
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Posting a video of the tree-planting ceremony on Twitter, Macron said the oak would be a "reminder, in the heart of the White House, of this bond that unites us".
Now the oak sapling is gone - at least temporarily. However, a Reuters photographer visited the site over the weekend and noticed that the tree apparently disappeared from where it was planted.
Almost 2,000 United States soldiers died in the battle north-east of Paris.
"It is in quarantine which is mandatory for any living organism imported to the U.S. It will be replanted afterwards", he wrote.
Macron presented Trump with the tree as a gift during his state visit to the United States. If nothing else, this is another demonstration of how the White House Communications Office doesn't seem to be on top of the game.