Nine people have been killed since protests erupted worldwide, seven in Afghanistan and one each in Somalia and Lebanon.
Denmark, where the 12 offending cartoons were first published, absorbed the brunt of Muslim anger, with attacks on diplomatic outposts, threats of economic boycotts, and the expulsion of Danish aid organisations from Chechyna.
Danish Prime Minister Anders Fogh Rasmussen said US President George W Bush had called him to give his backing.
"President Bush called me on the telephone to express his support and reiterated the support already received from the US, which we very much appreciate," Mr Rasmussen told a news conference in Copenhagen.
"We hope the international community will be able, together, to find a peaceful solution to this crisis," he said, calling for calm.
Attempts by Western leaders, religious figures and international bodies to appease Muslims infuriated by what they see as the blasphemous portrayal of their prophet seem to have fallen on deaf ears, as anti-Western protests remained virulent.
Protests continue
Several hundred demonstrators took to the streets of Bethlehem, chanting slogans calling for Denmark to apologise and setting fire to Danish and American flags in Manger Square.
Positions in the West have also hardened, with key officials expressing impatience with the continuing violence and demanding that foreign governments protect their embassies and consulates from rampaging mobs.
A few have suggested that some Muslim states, Iran and Syria in particular, have needlessly inflamed religious passions.
In Tehran, demonstrators throwing firebombs briefly stormed into the Danish embassy for a second consecutive day, with 20 to 30 protesters scaling the compound walls and another 300 outside hurling stones and Molotov cocktails.
The Tehran authorities had asked their citizens not to attack embassies, after the second assault on the Danish mission, the state news agency IRNA reported.
Iran suspends Danish trade
Besides summoning ambassadors of Denmark, Norway and Austria to express its anger over the caricatures, Iran has also announced a total ban on Danish imports as well as any other business dealings with the country "until further notice".
Iran is also raising charges on Danish-flagged vessels docking at Iranian ports, in moves slammed by the European Commission, which in turn confirmed that talks on boosting EU-Iranian trade will remain suspended until the escalating dispute over Tehran's nuclear plans is resolved.
Denmark, which has remained the top target for protests, scrambled to protect its nationals and cope with the diplomatic fallout of the cartoon crisis.
Irreverent cartoons of the Prophet Mohammed first appeared in the Danish daily Jyllands-Posten last September and have since been reprinted in many publications across Europe, causing outrage among Muslims.
Islam does not generally allow any depiction of the prophet, let alone caricatures of him, which it regards as blasphemous.