After announcing the intention to do so almost 2 years ago, The Budapest Development Center (BFK) has finally signed a contract with Főmterv to prepare a feasibility study for a railway tunnel under the Danube river.

Feasibility Study is required to examine the possible route, costs and benefits of the railway tunnel under the Danube between Kelenföld station and Nyugati railway station.

Following news is in English

https://dailynewshungary.com/budapest-rail-tunnel-project-enters-new-stage/

map is from BFK