2.3.1 – The Structure, Role and Powers of the Executive
Last week, like governments across the world, the British Government had to decide how they would respond and what role, if any, they would play in the situation. Initially, the British Government were keen to stress that they were not involved in any military action. Indeed, they briefed the media that they had prevented the US from using UK military bases to strike. However, as the situation developed, Keir Starmer confirmed British forces were actively deployed in what he described as a defensive role:
“Our forces are active and British planes are in the sky today as part of coordinated regional defensive operations to protect our people, our interests and our allies — as Britain has done before, in line with international law”
As would be expected given the enormity of events, Parliament discussed this on Monday when Keir Starmer gave a Ministerial Statement followed by X minutes of questions. However, Parliament was not able to vote on the deployment of military forces. This is because the deployment of military forces is a royal prerogative power. As the power emanates from the monarch, not Parliament, Parliament does not have the constitutional right to be consulted on the use of military forces. In some cases, Prime Minister’s have voluntarily decided to allow Parliament to vote on military action. Examples of this include:
Iraq (2003) – Tony Blair held a vote in Parliament on the deployment of military troops for the invasion of Iraq. It passed by 412-149.
Syria (2013) – David Cameron held a vote on whether to respond militarily to President Assad of Syria using chemical weapons against his own people. The military response was denied following a vote of 285-272.
Prime Minister’s may do this for a number of reasons, including:
Democratic Legitimacy – Allowing Parliament to vote on military action will likely reinforce the case for military action as it is backed by a democratic mandate.
Political Risk Sharing – Allowing Parliament to vote on military action means that the political risk if it backfires is somewhat shared with the legislature.
Party Management – Allowing a vote in Parliament may enable them to better manage any internal dissent to the action.
However, equally, there have been many occasions when Prime Minister’s have not allowed Parliament to directly express its view.
In the past, some political figures have called for a War Powers Act, piece of legislation that would remove the right of the Prime Minister to unilaterally order military action and would instead make it contingent on parliamentary approval. Most famously, Jeremy Corbyn called for this in April 2018 when Theresa May ordered military action against regime of President Assad. On Wednesday 4 March 2026, Corbyn presented the Military Action (Parliamentary Approval) (No. 2) Bill to the House of Commons, with a second reading scheduled for Friday 17 April. The purpose of the Bill is to:
‘Require parliamentary approval for the deployment of UK armed forces and military equipment for armed conflict; to require parliamentary approval for the granting of permission by Ministers for use of UK military bases and equipment by other nations for armed conflict; to require the withdrawal of that permission in circumstances where parliamentary approval is not granted; to provide for certain exemptions from these requirements; to make provision for retrospective parliamentary approval in certain circumstances; and for connected purposes.’
Yet, a fundamental argument against this would that it would interfere with the ability of the UK to respond quickly and effectively to emerging threats. In the case of the action over Iran, Starmer would argue that he had to acted decisively to ensure the protection of British nationals in the region. Consequently, the ability of the Prime Minister to unilaterally order military action is unlikely to change.