US says it saw preparations for possible Syria chemical attack

A warning from the White House to Syrian President Bashar Assad about another possible chemical weapons attack was also aimed at two of Assad's key backers, Russian Federation and Iran, the U.S ambassador to the United Nations said Tuesday.

A Monday evening statement by White House Press Secretary Sean Spicer said the USA had "identified potential preparations for another chemical weapons attack by the Assad regime that would likely result in the mass murder of civilians, including innocent children".

"If ... Mr. Assad conducts another mass murder attack using chemical weapons, he and his military will pay a heavy price", the statement warned.

The Pentagon says the US has seen chemical weapons activity at a Syrian air base that was used for an April sarin gas attack.

Meanwhile, a US-led coalition air strikes killed almost 60 people at a Syrian prison run by the Islamic State group, a monitor said on Tuesday, as Washington insisted the jihadists remain its only target.

The Kremlin is dismissing the White House's warning that the Syrian government is preparing a new chemical attack and that President Bashar Assad and his military "will pay a heavy price" if it goes ahead.

The US launched a fierce riposte in the aftermath of the chemical attack launched by Assad's forces in April - which was condemned across the world - and says it will not hesitate to take action should another similar strike take place.

A non-governmental source with close ties to the White House said the administration had received intelligence that the Syrians were mixing precursor chemicals for a possible sarin gas attack in either the east or south of the country, where government troops and allied forces have faced recent setbacks.

The U.S. strike in April was the first direct American assault on the Syrian government and Trump's most dramatic military order since becoming president.

United Nations Ambassador Nikki Haley put a finer point on Monday's warning, tweeting that "Any further attacks done to the people of Syria will be blamed on Assad, but also on Russia & Iran who support him killing his own people".

The U.S. struck the base in April after a gas attack killed 89 people in the rebel-held town of Khan Sheikhoun in northwestern Syria.

A senior Russian lawmaker accused the US of a "provocation".

A Pentagon spokesman, Navy Capt. Jeff Davis, said the US had seen "activity" at Shayrat airfield that "indicated active preparations for chemical weapons use". The U.N. has blamed three attacks on Assad's government and a fourth on the Islamic State group.

The US attack on the Syrian air base came after years of heated debate and deliberation in Washington over intervention in the bloody civil war.

Today's Pentagon statement clears up confusion in earlier reports suggesting-or flat out saying-that Pentagon and State Department officials didn't know this was coming.

President Donald Trump has said he won't stand for Syria's use of chemical weapons, which are banned under global law and are particularly worrisome in the Arab country because they could fall into extremists' hands.

The strong wording of the White House's statement drew a reaction from Russian Federation, a key ally and military partner of Assad's government.

Assad was seen Tuesday climbing into what observers described as a Russian-made Sukhoi Su-35 fighter jet at Syria's Hmeymim Air Base near the western seaboard city of Latakia.

The Syrian government was supposed to have destroyed its chemical weapons stockpiles after worldwide inspectors visited the country between 2013 and 2014.

Ali Haidar, the minister for national reconciliation, told The Associated Press on Tuesday that the White House statement foreshadowed a "diplomatic battle" that would be waged against Syria in the halls of the United Nations.

The statement was issued without further explanation.

On Tuesday, deputy White House spokeswoman Sarah Huckabee Sanders said "all relevant agencies. were involved in the process from the beginning".

Syrian activists say an airstrike targeting an Islamic State-run jail in eastern Syria has killed at least 42 prisoners. An anonymous White House official criticized anonymous "leaks" that maintained the Pentagon, the State Department and spy agencies were kept out of the loop on the decision to issue the warning to Assad.