13 Feb Government Foreign Policy Must Reckon with an Increasingly Muscular Parliament

As Keir Starmer set out in his speech on Greenland, in an increasingly volatile world, “geopolitics is not something that happens somewhere else”. Events abroad impact on the UK economy, energy prices, domestic security and politics. At the same time, parliament, which has historically had little say over the foreign sphere, is developing more constitutional powers on foreign policy, and has grown increasingly rebellious. In this context, both government and MPs will have to change how they think about foreign policy, and, crucially, how foreign policy decisions are made.

Historically parliament has had little say on foreign policy

Parliament has historically had little constitutional input on the actions of the government on the global stage. Most powers to act internationally, to do things like make war, deploy troops, or sign international treaties are done through the Royal Prerogative, powers conferred to the crown but exercised by ministers rather than parliament.

This means parliament does not have a clearly defined or codified constitutional role in diplomacy and foreign affairs. While there are mechanisms for scrutiny, the Foreign Affairs Committee, debates, and questions from MPs that can help to set the tone of debate and apply pressure to government, there are few hard levers available for parliament to restrain the government.

Shifts in convention, and a more muscular parliament mean MPs will continue to have a greater say in foreign affairs

However, in the past decade and a half, new conventions and laws have granted parliament more say in some key areas of foreign relations. Since 2010, the House of Commons has had the ability to object to the ratification of treaties, which can delay, but not block them, although they have never done so. Since 2020 the House of Lords has also had a dedicated International Agreements Committee to consider all treaties. While input remains limited, especially in comparison to other countries, there has been some expansion in parliament’s say.

Convention has shifted on foreign engagement too, and since 2011, there has been a convention that the House of Commons should have a debate on foreign deployments. The first real use of the convention came in 2011 when MPs voted to authorise strikes in Libya. Then, in 2013 the government was defeated in a vote on military action in Syria to prevent the use of chemical weapons, although MPs later voted in favour of strikes in 2015.

This is an emerging convention, and so its parameters have not been clearly set. Indeed, there are almost as many instances where the convention hasn’t been followed – when then Prime Minister Theresa May launched strikes in Syria in 2018 and Prime Ministers Rishi Sunak and Keir Starmer both launched strikes in Yemen against the Houthis without any debate or vote beforehand. Despite a lack of clarity on this convention, there will be an expectation that major foreign deployments beyond just airstrikes will see parliament consulted. Most recently, the Prime Minister committed to a vote in parliament on any deployment of troops to Ukraine as part of a peace deal.

This is not to say that parliament is now dictating foreign policy, but rather it has more capacity to have an impact.  What is perhaps more relevant is the power and willingness of this current crop of Labour backbenchers to push back against the government and force it into concessions, albeit solely on domestic policy so far. This has happened through formal mechanisms such as on welfare reform and the opposition’s humble address last week to force the release of documents relating to Peter Mandelson’s appointment as Ambassador to the United States. But we have also seen backbenchers push policy changes without a direct parliamentary mechanism. The decision to drop the two-child benefit cap came from pressure and discontent from MPs behind the scenes, rather than amendments or debates in the house. While they have not yet extended this pushback to the government’s foreign policy,

MPs will see issues of foreign policy on the doorstep increasing

These concessions have all been driven by electoral nervousness among MPs, a sense that the government is pursuing policies that will affect them and their party’s chances of re-election. MPs will always be focused on the bread-and-butter issues in their constituencies. Westminster’s approach to China or NATO is not going to overtake potholes and bin collection on the doorstep any time soon. However, in an increasingly volatile world, MPs will be recognising the impact that events abroad can have on their re-election prospects and their pushback on the government’s domestic agenda may extend to foreign policy.

The actions of the Trump administration have managed to elicit a strong reaction from voters across the globe. Not least two centre-left parties in Australia and Canada flagging in the polls were able to turn results around in part due to the United States President’s actions.

In 2024 we saw the impact that foreign policy issues can have with Shadow Work and Pensions Secretary Jonathan Ashworth losing his seat to a pro-Palestine independent, and Health Secretary Wes streeting came within a whisker of losing his.

As we edge toward an election in 2029 or earlier, foreign policy choices by the government will increasingly weigh on the minds of MPs, both for hot button issues driving votes, but also how the UK’s actions on the world stage can affect the price of goods, energy or interest rates.

Government will have to improve its engagement of MPs on foreign policy

In this context, it is important for government to have a strategy to keep MPs on side for its foreign policy ambitions. This is both on defence spending where MPs have a direct say, but also its relationship with the United States, Europe, China and the wider world. This crop of MPs has shown a willingness to make life difficult for the government, and with increasing parliamentary power over foreign policy, this is an arena where government may be forced into yet another damaging U-turn.

This is not a case of a whipping operation on foreign policy, but the government’s agenda will need a strategy for MP engagement. FCDO ministers and their PPSs will need to be in parliament explaining their choices and ensuring backbenchers feel heard. In the last few weeks, we have seen the government making difficult strategic choices in its response to the Trump administration and the Prime Minister’s visit to China. Keeping members in the loop and on side will be essential to navigating the twists and turns of a volatile world.

This approach can be mutually beneficial. MPs are a conduit between the public and government through their constituencies. As BFPG has long argued, government needs to do more to bring the public along on national security and defence, and their backbenchers can be valuable allies in that strategy. It is far better to be engaging now, than scrambling to bring MPs on side when facing a rebellion in a moment of geopolitical crisis.