The coalition in Iraq wants its troops to remain under their own jurisdictions after the handover of power.
BBC political correspondent Gary O'Donoghue looks at the issues surrounding the creation of a soveriegn Iraq.
What laws are coalition forces subject to?
Coalition forces are currently subject to something called Order 17.
Order 17 refers to an agreement signed by the Coalition Provisional Authority giving American and British troops protection.
That will now be extended to the new multi-national force made up of British and American forces which will remain in Iraq at the invitation of the interim government.
What happens after 30 June?
The last day of June has been set as the date for the handover of sovereignty to an interim Iraqi administration.
At that point, the administration willl be the legal authority in the country, though just how much control it will have over coalition forces is unclear.
Is this request for immunity a normal one for armed forces to make?
The British government stresses that soldiers will not be "immune" from prosecution.
In the event of crimes or misdemeanours they will be subject to military law and British law.
Is the timing of the request controversial?
It's a difficult time for this issue to be raised in that the abuses of Iraqi prisoners has made the whole subject of coalition behaviour extremely sensitive.
There was a good deal of anger in Iraq over the pictures of American troops abusing Iraqi prisoners and a lack of confidence in the judicial proces that followed.
The USA has already secured an opt out from the International Criminal Court. How does the coalition request fit in with this?
It's clear that America has an ongoing concern about potential prosecution of its troops in other jurisdictions.
That is why it refused to sign up to the International Criminal Court.
Both Britain and the US believe they have sufficiently robust judicial processes to deal with problems when they arise.
Many Iraqis would dispute that.