The US president claims that an attack could happen “very soon or not so soon at all!”

US President Donald Trump tweeted that he never “said when an attack on Syria would take place,” claiming it could it could “be very soon or not so soon at all!”

The tweet, sent early on Thursday morning, comes after a previous message in which Trump told Russia to prepare for missile attacks on Syria, which Russians officials in turn promised to shoot down.

The tweet caused many across the world to suspect that a US attack on Syria was imminent.

Russian Foreign Ministry Spokeswoman Maria Zakharova responded to Trump’s tweet by saying that “missiles should fly towards terrorists, not [Syria’s] lawful government, which has spent several years fighting against international terrorism on its territory.”

The social media back-and-forth came as the United States and several European countries threatened to take action against Syrian government forces in response to a suspected chemical weapons attack on the rebel-held town of Douma.

Russia is the main ally of Syrian President Bashar al-Assad, who has waged a seven-year civil war against rebel factions pushing for the overthrow of his government.

While tensions were high on Wednesday, Russia took steps to calm the situation, discounting “Twitter diplomacy” in a statement from Dimitri Peskov, a Kremlin spokesperson.

“We support serious approaches. We continue to believe that it is important not to take steps that could harm an already fragile situation,” Peskov was quoted as saying by Interfax.