In English we would say these two men are friends.
You could also say: "These two men are in a friendly relationship".
The sentence sounds strange and stilted in English. The number of these weird suggested translations is beginning to irritate me
I agree with the previous comments. The sentence is stilted and would not be said in English this way.
This sentence sounds ironic in English.
Are they lovers or pretend not to be... ;-)
...said the archaeologists after unearthing the grave of a gay couple buried together
in a relationship of a friendship of a relation on a ship of a friends hip