It's not been kegged long enough. Did you use a lager yeast? If so, you should not have even kegged this beer yet.
If you used an ale yeast, it's still very early. You are probably seeing yeast that's kicked up when you kegged.
Did you use Whirlfloc or something similar at the end of the boil? That will help clear your beer.
In any case, step away from the beer for 2 weeks, minimum. It'll clear on its own.