President Donald Trump on Sunday said Russian President Vladimir Putin and Iranian leaders were responsible for backing Syrian President Bashar Assad just hours after the Syrian government reportedly carried out a deadly chemical attack on a rebel-held area.

“Big price … to pay,” Trump tweeted, serving up rare public criticism of the Russian leader. But he did not elaborate on what he might do to punish Putin and Iran. His administration has slapped sanctions on Russian individuals and entities, expelled Russian diplomats and intelligence officers, and shuttered a Russian facility in Seattle.

Republicans and Democrats have pressured Trump to be tougher on Putin. But until recently, he had refused to publicly criticize the Russian leader amid the ongoing special counsel probe about 2016 election meddling and possible Trump campaign collusion with Russians. The president contends it would be best to have warmer relations with Putin.

But in his tweet Sunday, Trump pointed out that there were “Many dead, including women and children, in mindless CHEMICAL attack in Syria.” He urged “Animal Assad” to allow medical personnel to enter the area.

Many dead, including women and children, in mindless CHEMICAL attack in Syria. Area of atrocity is in lockdown and encircled by Syrian Army, making it completely inaccessible to outside world. President Putin, Russia and Iran are responsible for backing Animal Assad. Big price…

— Donald J. Trump (@realDonaldTrump) April 8, 2018

….to pay. Open area immediately for medical help and verification. Another humanitarian disaster for no reason whatsoever. SICK!

— Donald J. Trump (@realDonaldTrump) April 8, 2018

Early in his tenure, Trump ordered a cruise missile strike on Syrian government targets after another chemical attack. But he gave no indication Sunday he is poised to punish Assad this time with U.S. force.

The president did, however, place blame for Assad’s actions on another world figure: former President Barack Obama.

“If President Obama had crossed his stated Red Line In The Sand, the Syrian disaster would have ended long ago! Animal Assad would have been history!” he tweeted.

If President Obama had crossed his stated Red Line In The Sand, the Syrian disaster would have ended long ago! Animal Assad would have been history!

— Donald J. Trump (@realDonaldTrump) April 8, 2018

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