Britain’s international allies, led by the US, have responded with condemnation over the nerve agent attack in Salisbury.

The UK’s Nato allies rallied around Theresa May following her statement to MPs in which she said it was highly likely Russia was responsible for the use of chemical weapons against Sergei Skripal and his daughter Yulia.

Mrs May was assured of the backing of the US, Germany and France in calls to President Donald Trump, German Chancellor Angela Merkel and French President Emmanuel Macron, according to Downing Street readouts.

Number 10 said: “Chancellor Merkel condemned the attack and said she stood in full solidarity with the UK.”

While Mr Trump told Mrs May that “the US was with the UK all the way, agreeing that the Russian government must provide unambiguous answers as to how this nerve agent came to be used”.

And the Baltic states, which border Russia, also offered their support in the wake of the attack.

Latvia said it was prepared to offer the “required support” and urged Nato and the EU to agree on action.

A statement said: “The Latvian Ministry of Foreign Affairs condemns in the strongest terms the use of chemical weapons in Salisbury, the United Kingdom, on March 4.

“Those who planned and carried out the attack in the territory of a NATO member state must receive an appropriate and strong response.

“Latvia supports the UK’s efforts of carrying out an investigation into the circumstances of the perpetrated crime.

“This incident confirms the necessity for stepping up the implementation of the Chemical Weapons Convention to prevent the use of chemical weapons.”

Lithuania issued a statement which said: “The Lithuanian Foreign Ministry expresses strong solidarity with the United Kingdom following an audacious criminal act – the poisoning of a former military intelligence agent Sergei Skripal and his daughter.

“The Lithuanian MFA stresses that the use of a military-grade nerve agent within NATO territory represents an exceptional case, making it essential to identify the perpetrators and bring them to justice immediately.

“We call for a joint NATO and EU response.”

And Estonia said it was “disturbed” by the case and the state had “every confidence” in the investigation.

Estonian foreign minister Sven Mikser said: “This attack is a brutal violation of international law and order and demonstrates complete disregard for human life and suffering.

“Perpetrators of this heinous crime must be held accountable. We call for the full co-operation of the international community in this regard.

“We call on Russia to reassure the international community of its declaration of full destruction of its chemical weapons stockpile in October 2017 and that the integrity and effectiveness of non-proliferation regimes will be upheld.

“We offer our utmost support to our ally and friend the UK in its efforts to resolve the issue.”