UK Prime Minister Andy Burnham declined on Sunday to express support for a third runway at Heathrow Airport, saying he would wait for the results of an ongoing consultation before taking a position on the £33bn project approved by his predecessor, Keir Starmer [Source: BBC Business]. The decision leaves the future of Britain's largest infrastructure project in question, with Burnham suggesting he could yet block plans that had previously secured government approval [Source: Bloomberg].
The political uncertainty compounds a separate operational setback: Heathrow Airport has confirmed that its third runway will not be operational until at least 2039, a four-year delay from the government's original 2035 target. The airport said it now expects to secure planning permission by 2029, with the runway to open 'within a decade' of that milestone. A Heathrow spokesperson described the scheme as a national project that is 100% privately financed and said it would support at least 108,000 new jobs. A Department for Transport spokesperson noted that there is currently no live planning application for a third runway and declined to comment on ongoing consultation processes.
The delay and political ambiguity carry particular relevance for International Consolidated Airlines Group (IAG.L), the parent of British Airways and Heathrow's largest airline customer, which has long argued that the airport's two-runway constraint limits its competitive position. Ferrovial (FER.MC), which retains a residual minority stake in Heathrow following the sale of a larger shareholding to Ardian and Saudi Arabia's Public Investment Fund in December 2024, also has exposure to the project's outcome. No market-reaction data on either ticker was available at the time of publication.
Heathrow is the UK's busiest airport and Europe's busiest, serving more than 80 million passengers annually across just two runways. The expansion programme has a protracted history: the Airports Commission backed a third runway in July 2015, the government approved the plan in October 2016, and the Court of Appeal subsequently reversed the decision on environmental grounds before the UK Supreme Court lifted that ban in December 2020. Heathrow's board approved investment to begin work on a planning application in January 2026, and formal expansion plans were submitted to government in July 2025. The project's ownership landscape shifted materially in December 2024, when Ardian and Saudi Arabia's Public Investment Fund closed the acquisition of 22.6% and 15% stakes respectively in Heathrow for a combined US$4.12bn, making Ardian the airport's largest shareholder.
Sources: Bloomberg, BBC Business, The Guardian, Hexham Courant, BBN Times