By Jonathan Marcus BBC Defence Correspondent

There are growing signs that the United States is putting into place the necessary equipment for an eventual attack upon Iraq.

At least two large cargo ships have been hired to carry military supplies to the region, according to Pentagon reports, and the US Air Force is also stockpiling munitions and equipment at its key bases in the Gulf.

But even as the preparations continue, so too does the debate on the wisdom of any attack.

The Bush administration may be just beginning to realise the extent of the opposition to its plans to remove the Iraqi leader Saddam Hussein from power.

Preparations

Pentagon sources indicate that logistical preparations are underway.

The Bush administration's plans have met domestic opposition

The Pentagon has hired one large transport ship to move additional armoured vehicles to the Gulf region, and another will be heading that way for a pre-planned military exercise later this year.

Additional pre-positioned equipment may also be moved to the Indian Ocean - a relatively short steaming distance from the Gulf.

At the moment this is all being presented as prudent planning and housekeeping. Certainly, no green light has been given for any attack plan.

But it is also part of an elaborate psychological campaign, both to prepare the US and its allies for a possible war and to put additional pressure on the Iraqi regime itself.

Domestic dissent

But there are also contrary signs suggesting the Bush administration may be slowly backing away from a full-scale conflict with Iraq.

The level of opposition from America's friends and allies in Europe and the Gulf is one factor.

More important is the lack of consensus in Washington itself, especially on Capitol Hill.

Some powerful voices - including veteran foreign policy experts on the Republican side of the political spectrum - have urged caution. The administration has been slow to set out its policy for Iraq after Saddam is removed, and some critics say this is because no such plan exists.

In the absence of any convincing scenario for a post-war Iraq, a military campaign to oust Saddam Hussein may become politically impossible to carry out.

But that of course is not the message that the Bush administration wants the world to hear.