President Trump has met with Secretary General Jens Stoltenberg of NATO in Washington
The President refused to pull punches when he spoke of the "murderous" regime of President Bashar al-Assad.
He condemned what he called the "barbaric killing of children and babies" and thanked Nato members for standing by him in the joint press conference at the White House.
Speaking about relations with President Putin Mr Trump said there were problems.
He said: "Right now we are not getting along with Russia at all – we may be at an all time low.
"Russia is a strong country. The US is a very strong country.
"We are going to see how that all works out."
President Trump and Jens Stoltenberg met in the Oval Office while United States Secretary of State Rex Tillerson took part in a frosty meeting with President Putin.
Donald Trump grins as he meets Secretary General Jens Stoltenberg of NATO
Russia was left furious last week when Trump ordered the bombing of an airbase in Idlib Province, Syria, to take out a strategic air base.
The Republican leader of the US ordered multiple strikes after images of children dying in the street after a chemical weapons attack emerged.
Russia and its ally, president Bashar al-Assad of Syria denied the Syrian regime had attacked civilians.
Putin accused the US of undermining Moscow's strategic missions in Syria.
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Today's meeting marked 68 years since the signing of the North Atlantic Treaty.
President Trump said: "Nato allies defeated communism and liberated captive nations of the cold war
"It secured the longest unbroken period of peace Europe has ever known.
"Our common security is always number one and our common devotion to human dignity and freedom."
Chief Stoltenberg met with Donald Trump in the White House
Mr Stoltenberg praised Mr Trump for his "dedication" to Nato, including supporting Montenegro joining this week.
The Secretary General said Europe and the US are united by their membership.
He said: "Peace in Europe is important for the security and prosperity of North America.
"A strong Europe is good for the United States."
Chief Stoltenberg said the pair shared an "excellent and productive" meeting with Trump.
He said: "Nato must do more in the global fight against terrorism.
"Training local forces is one of the best weapons we have.
"Nato has the experience, expertise and staying power to make a real difference."
Again, the pair said every member of Nato must pay its fair share – set at two per cent of the country's GDP.
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