With three self-proclaimed “governments” and umpteen other regional factions of note, Libya is a difficult country to figure out for outside observers. But with Western nations openly talking about an invasion, everyone seems to recognize that being seen as the “world’s choice” could confer some big benefits on them.
This is fueling multiple factions to make pushes against the largest ISIS-held city in the country, the oil port of Sirte, with each believing that getting there first and establishing themselves as the foremost anti-ISIS faction would win them a lot of international legitimacy.
This appears to be a recognition not only of the factions attacking Sirte, but of the UN-backed “unity government,” which has no military to speak of, and is pointedly warning those other factions against attacking Sirte without first pledging loyalty to them.
The “unity government” is hoping its existing international support means that when the invasion comes, it comes to prop them up, but if someone else starts looking like a more convenient ally, they also recognize the very really possibility that the West could change their minds and back somebody else.