Kim Kardashian flashes her toned leg in thigh-high split black dress as she steps out to celebrate Khloe's 30th birthday in NYC

She took the plunge in a low-cut frock for a lunch with her sisters in New York earlier on Thursday.

But Kim Kardashian was all about the leg later that evening.

The 33-year-old donned a fitted black frock that sported a thigh-high slit as she arrived at the Gansevoort Hotel in Manhattan, ready to begin celebrations of her sister Khloe's 30th birthday party.

The reality star showed off her toned leg in the racy dress, which sported a halter neck and three gold buttons above the slit.

Kim added black strappy heels but kept the rest of her accessories to a minimum, allowing the frock to take centre stage.

The mother-of-one wore her dark hair loose and sleek and opted for a sultry smokey eye and nude lips.