While the US has engaged in high-profile diplomacy at the United Nations, behind the scenes US officials have been sending a tough message to the six smaller countries whose support they need for a new resolution on Iraq.
The art of persuasion in China
As Colin Powell travelled to China to ensure that it does not veto the second US resolution, other officials have been despatched to Latin America and Africa to try and secure their votes amid allegations of dire threats and generous promises of aid.
The full-court press is designed to secure the votes of Angola, Guinea, Cameroon, Mexico, Chile, and Pakistan - all non-permanent members of the Security Council.
The US needs nine votes out of 15 to pass its new resolution, and so far can only count on Britain, Spain and Bulgaria for support.
Of the other security council members, Syria, Russia, Germany and France are opposed to the new resolution, and China can at best be expected to stay neutral.
So the US must gain the votes of at least five of the other six non-permanent members, and prevent a veto by Russia, China, and France - permanent members of the council who with the power to block.
The vote of Pakistan - a staunch US ally but a Muslim country with much popular opposition to the US role in Afghanistan and the Middle East - is at best likely to be an abstention.
Surprisingly, the vote that is proving hardest for the US to secure is that of its normally close ally, Mexico.
Once Mexican-US relations were top of the agenda for President Bush, who met his newly elected Mexican counterpart Vincente Fox within the first month of taking office.
But since the terrorist attacks of 11 September, US interest in Latin America has waned, and Mr Bush's proposal to give an amnesty to illegal immigrants from Mexico has been withdrawn.
With more than 80% of Mexicans opposed to the war, Mr Fox is under intense domestic pressure to stand up to the United States.
He is also tied down by a diplomatic deal with Chile, the other Latin American state on the Security Council, to abstain in any vote if the five permanent members did not reach agreement.
On the other hand, the US is putting intense pressure on Mexico, and Spanish Prime Minister Jose Aznar joined in the lobbying efforts on his way to visit President Bush in Texas.
The US State Department has denied reports that Undersecretary of State Marc Grossman travelled to Mexico with a tough message for the Mexican government.
Press reports suggested that the US told Mexico would pay a "very heavy price" for not going along with the resolution.
Much of Mexico's trade is with the US, and despite a free trade pact, there are still a number of disputed areas that could prove troublesome, as well as immigration issues.
Meanwhile, Assistant Secretary of State Walter Kansteiner was diverted from a trip to South Africa to visit the three African nations with the promise of future aid if they would back the US.
He met Angola's president, Jose Eduardo dos Santos, on Thursday, and discussed both the need to stand up to Saddam Hussein and the help Angola needed to rebuild its war-torn economy, before flying to Conakry in Guinea on Friday.
Complicating the US task in Africa is the role of France, which recently hosted a summit of 50 African nations, all of whom - including Cameroon and Guinea - pledged to back the French position on giving the inspectors more time.
The French also promised additional aid and trade concessions to African states.
Any diplomacy of this nature is likely to be counterproductive if it receives too much publicity - especially given the widespread public scepticism about US motives around the world.
But the evidence suggests that the US is beginning to exert its diplomatic weight far more forcefully than earlier in the crisis.
As well as despatching Mr Powell to China, Undersecretary of State John Bolton is visiting Moscow this week, with the aim of encouraging Russia to abstain rather than vote against the US resolution.
That, at least, would isolate France if it still insisted on using its veto.
But, with time running out, US diplomats still face a daunting task.