Khat, also known as cathonine, is popular in parts of the Middle East and Africa, where users chew the leaf to release stimulants that produce a mild high.
Home Secretary Theresa May noted the recommendations against a ban, but said in a written statement today the decision is "finely balanced" and takes into account expert scientific advice.
She said banning khat will "send a clear message" that Britain is serious about stopping illegal trafficking of khat.
She said that since the whole of northern Europe and most other EU member states have banned khat, failure to act would put Britain at risk of becoming a trafficking hub.