US President Barracks Obama said a new round of sanctions will continue to ratchet up the pressure on Russia.
The US leader said existing sanctions have already made the Russian economy even weaker.
He added: "If Russia continues on this current path, the costs on Russia will continue to grow."
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Prime Minister Abiy Ahmed called the blast a ‘well-orchestrated attack’.
An explosion at a rally he was speaking at was the narrowest of escapes for Zimbabwean President Emmerson Mnangagwa.
President Emmerson Mnangagwa said ‘it is not my time’ after the blast at a Zanu PF event in Bulawayo.