The armed forces are to receive another £800m from the Treasury next year to pay for military operations in Iraq and Afghanistan, as the total cost of the two conflicts approaches £6bn.
Gordon Brown also allocated £200m “to promote peacekeeping in the most troubled countries of the world”.
The Ministry of Defence has a yearly budget of £33bn, but the Treasury sets aside a special supplement to pay for Iraqi and Afghan operations.
The £800m allocation is lower than last year’s £980m, but the MoD has shown a tendency to revise the figure upwards as the year progresses and new military needs are identified.
For instance, the MoD recently returned to the Treasury to say it would need £1.3bn for the year just gone, rather than the £980m set aside originally.
The MoD said the increase in spending last year was a one-off spike that was explained largely by the need to upgrade equipment for the thousands of troops about to be posted to Afghanistan.
The UK is sending more than 3,300 troops to the Helmand province in the south of Afghanistan, against a background of growing violence in the region.
Another 1,000 troops will be sent to Kabul in May to assume command of Nato headquarters.
However, the bulk of the money spent last year, £1.1bn, went to Iraq, with just £220m going to Afghanistan. The amount spent on Iraq was higher than the £910m spent the previous year, because of the worsening security situation.
Much of the extra capital expenditure went on “urgent operational requirements”, including measures to protect troops from the increasingly sophisticated roadside bombs used by insurgents in Iraq.
The UK has now spent £4.2bn on military operations in Iraq over the past four years, and £644m in Afghanistan. This year’s spending will take the total in both countries to more than £5.6bn.
MPs on the parliamentary defence committee have criticised the MoD for not providing enough details on its spending in Iraq and Afghanistan.
Last week, the committee said: “The MoD must recognise that the agreement of the Treasury [on its spending plans] is not a substitute for parliamentary approval.” It called on the MoD to provide a regular breakdown of costs on operations in Iraq and Afghanistan “in the same way as it provides information to the Treasury.”
Decisions on whether to reduce troop commitments in Iraq will influence whether the MoD needs to ask for more than its £800m allocation later in the year.
John Reid, the defence secretary, said recently that troop numbers would be cut from 8,000 to 7,200 by May, but warned this was not the beginning of a full handover of some provinces.
Some senior Iraqi politicians claim the country has descended into full-scale civil war, although the US and the UK both deny this.
While British politicians are keen to reduce troop numbers further in Iraq, they must weigh this against any perception that they are cutting and running.
While it has not provided an estimate of probable future costs in Iraq, the MoD has said it will spend about £1bn in Afghanistan in the next five years.
Separately on Wednesday, the Treasury said it would allocate another £100m to the MoD this year to spend on modernising its forces. The army is being reshaped as an overseas expeditionary force and has embarked on a cost-cutting drive to introduce £2.8bn of yearly savings by 2008.
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