Joint stock company JSC Ukrainian Railways is inaugurating a railway line built to Europe’s track width standard with funding from the European Union. The new 22 km, 1435 mm gauge line connects the western Ukrainian cities of Uzhhorod and Chop, facilitating freight and passenger rail connectivity...
This is the second one, actually. Hungarian trains started serving Mukachevo already years ago.
Ah yes, I see it on openrailwaymap, which also indicates mixed gauge all the way along the Tisza valley to Vinohradiv, also a ukranian gauge line from Uzhhorod to Kosice - are these still operating ?