Paris threatens Alstom over RER B train delays
Paris transport authority Île-de-France Mobilités (IDFM) has imposed an emergency action plan on Alstom after new MI20 trains for the RER B slipped to 2029 delivery – four years behind the original 2025 schedule. The EUR 2.5 billion contract for 146 trains is one of the largest in Europe, covering the continent’s busiest commuter line with more than one million daily passengers.
Binding milestones after independent review
The confrontation escalated during a board hearing this week where IDFM president Valérie Pécresse described the new forecast as “unacceptable” for a line connecting Charles de Gaulle and Orly airports with central Paris. Independent analysis by Yves Ramette and consultancy Finexi confirmed that without intervention, the first trains would not enter service until September 2029.
In response, IDFM has introduced an emergency plan that sets binding production milestones, increases governance oversight, and strengthens industrial processes. The authority underlined its leverage as Alstom’s largest single customer, warning that further delays risk undermining the parallel Nexteo digital signalling upgrade designed to raise RER B capacity.
Alstom under pressure on multiple fronts
Alstom CEO Henri Poupart-Lafarge acknowledged “inventory problems” across the portfolio and pledged that first MI20 assembly would begin by April 2026, with service entry before the end of 2028. Even under this revised plan, the project remains three years behind its original schedule.
The MI20 difficulties add to a series of delayed programmes since Alstom’s 2021 acquisition of Bombardier Transportation. Delivery of TGV M high-speed trains has slipped from 2023 to 2026, while regional contracts in Germany, Spain and Canada face similar backlogs. Analysts warn that structural integration challenges and supply chain bottlenecks are eroding customer confidence across multiple markets.
Political and financial sensitivity
The RER B situation carries particular weight because of the line’s critical role for daily commuters and international travellers. The route handles more passengers than the entire French high-speed network, making reliability a political priority. Any extended disruption risks reputational damage for IDFM and for the government in advance of municipal and national elections.
Financially, the EUR 2.5 billion order is central to Alstom’s order book. Persistent slippage could impact cash flow recognition and strain the company’s ability to manage debt taken on during the Bombardier acquisition. Investors are closely watching whether Alstom can stabilise its delivery pipeline without further state support.
Timeline of shifting forecasts
2019 – Contract signed for 146 MI20 trains, entry to service planned for 2025
2022 – Delivery postponed to 2027 after early integration issues
2025 – Independent review projects first service in 2029 without corrective action
2026 (planned) – First assembly milestone due in April under emergency plan
2028 (revised Alstom target) – First trains expected to enter passenger service
The repeated revisions highlight both the technical complexity of the project and the wider difficulties Alstom has faced in aligning inherited Bombardier facilities with its own production system.
Why it matters
Passenger impact: Over one million daily travellers on RER B face years more of overcrowding and service disruption.
Policy risk: Delays threaten the credibility of parallel digital upgrades like Nexteo, designed to boost capacity and punctuality.
Market signal: Alstom’s continued struggles raise questions about the company’s ability to deliver large-scale contracts, with potential consequences for future EU and international tenders.
What happens next
IDFM has made clear it will enforce the emergency milestones, with quarterly reporting obligations and direct oversight by its technical teams. Alstom must demonstrate progress by mid-2026 or face potential contractual penalties. For passengers, the risk is not only a delayed modern fleet but also slower capacity gains if train deliveries and Nexteo signalling are not synchronised.
Next update: The first binding milestone is scheduled for April 2026 when Alstom has pledged to complete the first MI20 assembly.