Again breaking with Russian leader Vladimir Putin over the situation in Syria, President Donald Trump on Wednesday taunted Moscow via Twitter, scoffing at talk by Russian lawmakers that their nation would stop any U.S. missiles which might be aimed at Syrian facilities in the wake of chemical attacks in that country by the Assad Regime.

"Get ready Russia," the President wrote on Twitter just before 7 am ET.

"You shouldn't be partners with a Gas Killing Animal who kills his people and enjoys it!" the President added, as he said U.S. ties to Russia were deteriorating.

It was almost exactly a year ago that the United States launched a series of Tomahawk cruise missiles from U.S. Navy vessels, striking a Syrian military base which officials said was involved in a chemical weapons attack.

The President's tweet was just the latest in an increasingly testy verbal back-and-forth between the United States and Russia; on Tuesday, the Russians vetoed an effort at the United Nations to launch a full inquiry into the latest chemical weapons attack.

During debate, the Russian Ambassador to the United Nations accused the U.S. and other Western nations of "trying to mislead the international community," arguing it was a step on the road to military action.

U.S. Ambassador Nikki Haley meanwhile accused the Russians of "protecting a monster," by giving their backing to Syrian leader Bashar al-Assad.

After months of tip-toeing around Russian leader Vladimir Putin on many issues, the President has been much more pointed in his criticism of Moscow since this latest gas attack - on Sunday, he specifically warned Russia and Iran that they would pay a "Big price" for backing Assad.

On Tuesday, the President scrapped his scheduled trip to South America for next week, as the White House said he wanted to remain in the United States to oversee any possible military response on Syria.

"President Trump will remain in the United States to oversee the American response to Syria and to monitor developments around the world," said Press Secretary Sarah Huckabee Sanders, who said the President had spoken with the British leader about Assad's "vicious disregard for human life."

In Congress, the latest tweets by the President left Democrats concerned.

"15 months in, and the Trump administration has no Syria strategy. Threats, tweets, one off strikes are not a strategy," said Sen. Tim Kaine (D-VA). "Baiting Russia is not a strategy."

Democrats also immediately dug out an old tweet by Mr. Trump - from 2013, during the Obama Administration - in which he criticized how the Democratic President was conducting policy on Syria.