So Tom Holland tweeted:

“One has to wonder which government could conceivably have put Spain up to doing this. Or perhaps Spain just has a particular interest in UK transport, who knows?”

Beats us.

Unless ….
https://www.reuters.com/article/us-britain-eu-spain-gibraltar/eu-leaders-to-urge-british-spanish-gibraltar-status-settlement-idUSKBN1JO0XS