Tony Blair has admitted that some Cabinet members have doubts about his handling of the Middle East crisis.
The prime minister said he was not surprised "there is anxiety amongst members of the Cabinet" over policy on the conflict in Lebanon.
But he said claims of a split between him and the Foreign Secretary Margaret Beckett were "complete rubbish".
He added he hoped there would be a UN resolution paving the way for a ceasefire in Lebanon within days.
Mr Blair conceded there were divisions within government over his refusal to criticise Israel's military action and back calls for an immediate ceasefire.
"It is not surprising to me that there are people who profoundly disagree with the policy," he said.
"Or that there is anxiety amongst members of the Cabinet; members of the Parliamentary Labour Party; people in the country. This is a very difficult situation."
Mr Blair said he was trying to bring the crisis to an end "by the only practical means I can think of" and said he hoped there would be a UN resolution paving the way for a ceasefire in Lebanon "in the next few days".
He repeatedly refused to condemn Israel's actions as disproportionate and denied his reluctance to call for an immediate ceasefire had given a "green light" to Israel to continue fighting.
"If the ceasefire is not on both sides, Israel will continue to take action. That's the reality."
Asked about his warning this week that Iran and Syria must stop supporting terrorism or they would "be confronted", Mr Blair said "no one was threatening military action" against the two countries.
But he said they had to help find a solution to the Middle East crisis, "not hinder it".
The West had to argue "more convincingly" for its democratic vision for the Middle East - as opposed to a region ruled by "secular dictators and religious fanatics," he added.
Mr Blair denied his words would be seen as part of a "religious war".
"How can it possibly be a religious war... when what we actually want is for Jew and Christian and Muslim to live in peace with each other as they do here in our country?"
On Iraq, Mr Blair said the comments in a leaked memo by departing UK ambassador William Patey, warning civil war was now a more likely option than democracy, were no different to what Mr Patey had already said publicly.
"However tough it is (in Iraq), we will see it through," he added.
Mr Blair returned from the US on Wednesday to criticism from senior figures in his own party over his Middle East policy.
Ann Clwyd, chairman of the Parliamentary Labour Party, said the "vast majority" of backbench Labour MPs wanted a ceasefire and former minister Joan Ruddock said there was "despair" in the party at Mr Blair's stance.
Liberal Democrat leader Sir Menzies Campbell said Mr Blair's approach "flies in the face of UK and world opinion".
Lord Hurd, the former Conservative Foreign Secretary, described the Prime Minister as "out of control" and having a "creepy" attitude towards the Americans.