Contributes to virulence by binding to the host IKBKB subunit of the IKK complex and preventing host NF-kappa-B activation in response to pro-inflammatory stimuli such as TNF-alpha or IL1B. Homodimers. Interaction with host IKBKB; this interaction inhibits host NF-kappa-B activation (By similarity). Belongs to the poxviridae B14 protein family.