In a move that is causing concern to the already over-stretched main contributors, particularly the US, Britain and Australia, key allies, such as the Netherlands, Ukraine and Poland, are ordering their forces to return home.

Under pressure at home, some countries, such as Portugal, withdrew their small contingent this year. Other key coalition partners, such as Italy, with 3,000 troops, face growing public pressure to withdraw their forces.

The pressure on the Government in Rome has intensified since the shooting this month by American troops of an Italian intelligence officer who had helped to free a hostage.

This week the Dutch contingent, which once numbered 1,500 troops and controlled the vast southern province of Muthana, lowered its flag and left, leaving the desert border territory to British forces.

Although Britain had hoped to cut the size of its contingent after the election on January 30, the Army has had to deploy reinforcements to fill the gap left by the Dutch retreat. Some 650 British soldiers, mostly from The Queen’s Dragoon Guards and The Princess of Wales’s Royal Regiment, have been sent to the area. They will work alongside 450 Australian soldiers who were ordered to Iraq by John Howard, the Australian Prime Minister, last month. The Anglo-Australian force will protect some 600 Japanese army engineers, who serve in the province but are barred from fighting.

The region in southern Iraq is relatively benign and British officials hope that once Iraqi forces have been trained, the area can be handed over to their control.

A bigger headache for the coalition is the reduction of the two main contributors to the central area south of Baghdad, a volatile insurgent area. Over the weekend, the first 150 Ukrainian troops packed up and headed home, with the remaining 1,500 to follow over the next six months.

The move leaves the Poles, the lead force in the area, badly exposed and they, too, have signalled that they are halving the size of their 1,700-strong force and changing the mission.

Jerzy Szmajdzinski, the Polish Defence Minister, said last week that Polish forces increasingly would concentrate on training Iraqi troops, with the aim of handing over security to them. But there are fears that this approach may be premature as the insurgency continues to make the country ungovernable.

Nevertheless, it may be difficult to persuade remaining members of the coalition to be in the country much beyond the end of the year, whether or not the Iraqi security forces are ready. Many contributing nations expect to have their soldiers home as soon as Iraq holds its second round of elections, scheduled for December, when a permanent government should be in place.

HOW THE NUMBERS ADD UP

STAYING: US 150,000 (military personnel); Britain 8,850; South Korea 3,600; Italy 3,000; Australia 900 (up to 1,350 by April); Romania 800, up to 900; Japan 600; Denmark 500; Bulgaria 380; El Salvador 380; Georgia 300, up to 800; Mongolia 180; Azerbaijan 150; Latvia 120; Lithuania 100; Slovakia 100; Czech Republic 90; Albania 70; Estonia 50; Tonga 40; Kazakhstan 30; Macedonia 30; Moldova 25

GOING: Netherlands 1,500; Ukraine (1,650 leaving by October); Poland 1,700 (reducing by half)

GONE: Spain 1,300; Thailand 460; Hungary 300; Honduras 370; Dominican Republic 300; Nicaragua 115; Portugal 127; New Zealand 60; Philippines 50; Norway 10

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