The Archbishop of Canterbury has led calls for Tony Blair and George Bush to demand an immediate ceasefire by Israel and Hizbollah.
Dr Rowan Williams accused Mr Blair of being out of touch with public opinion as people across Britain prepared to march in protest today at the carnage in the Middle East.
The demonstrations echo the backlash before the Iraq war began in March 2003 when millions demonstrated against British involvement in the invasion of Iraq. The issue of Mr Blair's adherence to the American line has dogged his premiership since.
The former Foreign Office minister Chris Mullin accused the US and British governments of standing by while the Israelis committed "war crimes".
As the demands for a change of British foreign policy raged, Mr Blair's official spokesman dismissed the calls by Dr Williams and others for a ceasefire, saying it would "make people feel good for a few hours" but was unlikely to have any lasting effect. "In what way is it in the interests of the Middle East to pretend that somehow or other calling for a unilateral ceasefire is actually going to help the situation?" the Prime Minister's spokesman said.
However, Dr Williams warned: "We really have to ask whether the governments of some Western countries are catching up with the consciences of their own people. They may have to reckon with the rising level of public despair and dismay and I hope that they will bring their influence to bear in moving towards a ceasefire."
Thousands of people are expected to join demonstrations across the country today to protest at the Israeli attacks on Lebanon.
The protests have been called by groups including the Stop The War Coalition and the Muslim Association of Britain to highlight "crimes against humanity".
A spokesman for the protest organisers said: "Israel's war in Gaza and Lebanon is escalating into an international crisis which could soon engulf the whole region.
"The promise by Bush and Blair in the lead-up to the Iraq war that their wars would bring freedom and democracy to the Middle East and peace to Palestine, have yet again been shown to be lies, just as the anti-war movement has consistently said they were."
Demonstrations will also be held in Birmingham, Bristol, Edinburgh, Exeter, Glasgow, Kirkcaldy, Manchester, Newcastle, Sheffield and York.
The Foreign Office minister Kim Howells was flying to the Middle East for talks with governments in the region. Mr Howells said: "The aim of these talks will be to work towards a lasting ceasefire, backed up by action not just words, which guarantees Israel's security and that of its neighbours."Reuse content