He told the programme: "Any visit that is happening now to the Ukraine is done on the invitation of the president of the Ukraine. Prime Minister Johnson received this invitation and he agreed. It might be a surprise for you but it is not a surprise for us. We were preparing for a while. This visit was very timely and very important in terms of war."
Mr Zhovkva described Mr Johnson as being "very supportive" during previous discussions before the war began about "the potential danger which Russian aggression might have".
Mr Zhovkva said many leaders are coming to Kyiv with their support now the war has begun but they have to come "not only with their show of support but something that will have meaning, which has results".
He said "we had results yesterday because the Prime Minister did not come empty-handed" and the political leaders talked about many things including military and financial support plus the further "rebuilding Ukraine when we will win so it was very timely and helpful".
Mr Zhovkva said: "Every visit, every phone call, every act of support counts and brings us to victory."
He said Mr Zelensky is determined to meet leaders in the capital, to speak to foreign parliaments and talk with the foreign leaders.