Cold War-style Checkpoint Charlie borders after Brexit will not be acceptable, Gibraltar’s chief minister has said.
Crossings must not be used as “choke points” for political reasons, Fabian Picardo added.
His territory has had a strained relationship with neighbouring Spain for many years.
He gave evidence on Wednesday to a Northern Ireland Affairs Committee investigation at Westminster into the Irish border and said he would visit the country soon.
Mr Picardo said: “Nobody is going to accept something which looks like, feels like, smells like Checkpoint Charlie.
“Don’t see a border as a way of creating conflict, that will only cause real hardship.”
Checkpoint Charlie in Berlin was the most famous crossing point between East and West Germany during the Cold War and came to symbolise divisions between the West and the Soviet Union.
Gibraltar, a tiny British overseas territory of about 30,000 people on the southern tip of Europe, voted overwhelmingly against Brexit.
It is not in the customs union and produces virtually nothing, importing its labour and goods.
It uses cameras and guards to police its short border with Spain, Mr Picardo said.
Around 13,000 people enter Gibraltar from Spain for work each morning.
There are two crossings over a frontier just three quarters of a mile long, one for commercial and one for non-commercial traffic.
Mr Picardo said it would be impossible to put Heathrow-style machine readers in place to force everybody to scan their passports.
Instead technology costing £200,000 to install checks traffic against Interpol lists of suspected criminals, while “trusted trader” status for large companies allows goods to pass through easily.
Earlier this year there was a row after draft Brexit negotiating guidelines published by the EU said Spain would be consulted on any decisions affecting Gibraltar.
The chief minister pledged to visit Northern Ireland in the near future and is scheduled to meet DUP leader Arlene Foster and Sinn Fein’s Michelle O’Neill as Brexit talks in Brussels intensify.