The Governing Council authorized this Tuesday, at the request of the Minister of Sustainable Mobility, the signing of a collaboration agreement between the regional Executive and the Provincial Council of Bizkaia. This agreement aims at the construction and financing of Line 4 of the Bilbao metropolitan railway, seeking to promote territorial cohesion through the train as a fundamental axis to structure Bizkaia in public transport, with its capital as a mobility hub.

The agreement stipulates that the Basque Government will cover 55% of the funding, with the Provincial Council of Bizkaia contributing the remaining 45%, up to a maximum of 200 million euros until 2032 for the provincial administration. The initial budget for the project is estimated at 412 million euros, a figure that may be updated based on the final construction projects, which are currently being drafted.

Euskal Trenbide Sarea (ETS), a public entity under the Department of Sustainable Mobility, will be responsible for the projects and construction of this new infrastructure. Line 4 will span 6.7 kilometers, connecting the upper southern neighborhoods of Bilbao, such as Irala and Rekalde, to the metropolitan railway system. It will feature six new stations at Deusto/University, Parque, Zabalburu, Moyua, Irala, and Rekalde. If all proceeds as planned, construction in Rekalde is slated to begin by the end of 2027.

Furthermore, the agreement includes provisions for necessary inter-institutional contacts to promote the transfer of the current C4f metric-gauge line, which connects the Enkarterri region with the historical territory's capital. This line's infrastructure remains under the control of the central Government through Adif and carries commuter trains, a service transferred to the Basque Executive in January 2025. The objective of the agreement is to boost the transfer of the C4f infrastructure so that Bilbao Metro Line 4 can utilize this existing network and extend to Enkarterri after its transfer.