BRITAIN’S “weak and rotten” government must not march behind US President Donald Trump into another disastrous Middle Eastern war, the Stop the War Coalition warned yesterday.

Convener Lindsey German condemned Foreign Secretary Michael Fallon’s craven support for Mr Trump’s latest threat to intervene in Syria’s civil war — on the grounds that the Bashar al-Assad regime is allegedly planning a chemical attack.

Following a statement on Monday from White House spokesman Sean Spicer saying the US had “identified potential preparations for another chemical weapons attack” by Syrian forces, Mr Fallon said the government “will support” US bombing in Syria.

The White House statement alluded to the incident in Khan Sheikhoun in Syria’s southern Idlib province in early April, where al-Qaida affiliated insurgents claimed air force jets dropped nerve gas.

Mr Trump ordered air strikes on Syrian troops in response.

But the US narrative on what happened in Khan Sheikhoun is highly contentious, with Syria and Russia suggesting at the time that a rebel-controlled chemical weapons store could have been hit in a conventional air strike.

Syrian rebels have been caught trying to cross the Turkish border with sarin gas, the nerve agent said to have been used in the attack, and veteran US investigative journalist Seymour Hersh has revealed in Die Welt newspaper that US intelligence was deeply sceptical of Syria’s responsibility — with one official calling it a “false flag” attack by al-Qaida.

Mr Spicer did not provide any evidence for his claims on Monday, although the Pentagon backed the White House yesterday, with spokesman Captain Jeff Davis claiming that the US had seen “activity” at a Syrian army base that “indicated active preparations for chemical weapons use.”

Speaking on BBC Radio 4’s Today Programme yesterday morning, Mr Fallon said: “As always in war, the military action you use must be justified, it must be legal, it must proportionate, it must be necessary.

“In the last case it was,” he claimed — although April’s attack and several on Syrian troops and aircraft since were conducted without the authorisation of the UN security council or a formal declaration of war.

“If the Americans take similar action again, I want to be very clear — we will support it,” Mr Fallon stated.

Ms German said: “While we oppose all chemical weapons attacks from whatever source, even some in the US military are sceptical about Trump’s evidence.

“The last thing the people of Syria need is more military intervention, which is taking the Middle East towards worse wars.”

Syrian National Reconciliation Minister Ali Haidar denied the US claims, saying the statement presaged a “diplomatic battle” against his country at the UN.

Kremlin spokesman Dmitry Peskov called the US threat “unacceptable” and challenged the reference to “another attack,” as the April incident had not been “independently investigated.”

He pointed to several confirmed chemical weapons attacks by Isis and other extremist terror groups, adding: “There is a potential threat of the repeat of such provocations.”