U.S. Ambassador to the United Nations Nikki Haley on Sunday hinted that Russia should brace itself for more economic sanctions after its continued support of Syrian President Bashar Assad, despite Assad's use of chemical weapons against his own people.

"Right now, they don't have very good friends. And right now, the friends that they do have are causing them harm," Haley said during an interview with "Fox News Sunday," referring to the Kremlin.

"I think they're feeling that, whether it's been ... the fact that we've sanctioned just recently the Russian oligarchs, which made their stock market plummet," Haley said, citing the U.S. supplying arms to Ukraine and the recent expulsion of 60 Russian diplomats as other examples. "Or whether it's the sanctions that are continuing to happen, which you'll see again on Monday."

U.N. Security Council members on Saturday rejected a Russian proposal to condemn the American-led attack on Syria, voting down the resolution in an emergency meeting.

U.S., British and French forces launched a military strike in Syria on Friday in response to reports Assad's government was behind an April 7 poison gas attack on the rebel-held city of Doumas, killing at least 40 people.

President Trump's outrage at Russian President Vladimir Putin's backing of Assad marks one of the first times Trump has been critical of Putin since assuming the presidency.

But Haley said Sunday that America's dynamic with Russia has "been changing over time."

"This is a very strained time between the United States and Russia," she explained, adding "everything that has strained this relationship has been on the side of Russia."