It's a good time for a diacetyl rest- I usually do one when the lager is at about 1.020. Bring the temperature up at least 10 degrees, and let it stay there until fermentation is finished and the buttery flavor is gone. It may take more than 48 hours to clean up all of the diacetyl. Diacetyl in large amounts tastes buttery, but in small amounts it presents as an oily mouthfeel or a slickness on the tongue. You want that completely gone before racking and lagering!
It will get worse during lagering, not better, so it's time to get rid of it now!