How do I bribe ships in Freeciv?

I am playing a self-imposed "single-city challenge" game (i.e. a game where I restrict myself to having only one city). Naturally, I built the city beside a sea to be able access to the rest of the world by ship. Unfortunately, I built my city in what turned out to be a landlocked sea (a large lake). As a result, the ships I currently have are not able to go to the open seas.

I am now considering bribing the ships (trireme, caravel, or transport) of other players to gain access to the open seas, but how can I bribe the ships of other players?

Freeciv version: 2.5.10

From Freeciv 2.6.0 onwards, it is possible to bribe ships.

Below is an example of bribing a transport. Note that the transport must be empty, otherwise the bribe will fail.

It's also possible to bribe other sea units (ironclads, battleships, submarines, etc.) as long as they are not loaded:

Side note: It's also possible to bribe aircraft.

Rules for bribing enemy units are (if you haven't altered them):

Either a Diplomat or Spy can bribe an other players unit.

Can't bribe a unit if:
Owner runs an unbribable government (e.g., democracy).
Player doesn't have enough gold.
It's not the only unit on the square
You are allied with the unit owner.

Otherwise, the unit will be bribed.
A successful briber will try to move onto the victim's square.

Quoted from: https://freeciv.fandom.com/wiki/Diplomatic_actions#Bribe_Enemy_Unit