Rishi Sunak is taking questions from MPs after the second misfiring of a trident missile in a row.
Labour has called for assurances over the effectiveness of Britain’s nuclear deterrent after an “anomaly occurred” during an exercise that took place on January 30 on board the nuclear-powered submarine HMS Vanguard.
It is said to be the second misfiring in a row, with a test launch of a Trident missile by the Royal Navy off the coast of the US in June 2016 also reported to have been a failure.
The PM will also face Labour and SNP calls for a Gaza ceasefire.
Scottish Labour members voted on Saturday to overwhelmingly back a motion calling for an immediate ceasefire between Israel and Hamas.
The move came after days of party debate on how to vote in Parliament on an SNP motion calling for a ceasefire since the outbreak of the conflict in October.
Wednesday’s debate will take place as thousands of pro-Palestinian demonstrators are expected to take part in a rally in Parliament Square.
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