This map shows the section of the M4 that is frequently congested, and that would be bypassed if plans for a 14-mile relief road went ahead.
The Welsh government has long pushed for a relief road in this area. Plans were shelved in 2009 after the projected cost of the project rose to £1 billion.
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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.