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The Syrian province of Idlib and surrounding areas are the last major enclave held by rebels opposed to Syrian President Bashar al-Assad, a close Iranian and Russian ally. Assad is reportedly preparing a phased offensive to regain the province. The US President wrote on Twitter: “President Bashar al-Assad of Syria must not recklessly attack Idlib Province. “The Russians and Iranians would be making a grave humanitarian mistake to take part in this potential human tragedy.

“Hundreds of thousands of people could be killed. “Don’t let that happen!” The message is being seen as a red line, with suggestions the President may retaliate to any attack on the province. Trump’s tweet comes a few days after Russia declared part of the Mediterranean would be “dangerous” while they hold a massive naval exercise.

Trump has warned Syria’s President Assad not to send a reckless attack to Idlib

The tweet is being seen as a red line, with suggestions the President may retaliate to any attack

Russian sources have claimed the military drills are needed ahead of the final assault on Syria’s rebels in Idlib. Kremlin spokesman Dmitry Peskov said: “This hotbed of terrorists in Idlib does really not bode anything good if such inaction continues. “The situation in Syria has a significant potential to become more complicated and the situation around Idlib leaves a lot to be desired.” Syrian Foreign Minister Walid al-Moualem said last week: “We will go all the way in Idlib."

Russian sources have claimed the military drills are needed ahead of the final assault in Idlib