The collusion could be in an explicit agreement, or in a more subtle form — known as tacit coordination or coordinated interaction.

这种串谋可以是一个很明显的协定，也可能是以较为隐蔽的方式。

youdao

"There is apparently a tacit agreement between both leaders, if not coordination, to engage in very intense PDA, " or public displays of affection.

WSJ: U.S., Israeli Leaders Seek to Bridge Divide