image captionLike many of Saturday's papers, the Daily Mail leads on former Downing Street adviser Dominic Cummings' denial over accusations he leaked text messages sent between Prime Minister Boris Johnson and businessman Sir James Dyson. The paper says Mr Cummings "unleashed an astonishing attack" on his former boss in a "devastating 1,100-word statement", calling it an "all out war" between the two. No 10 says ministers always obeyed codes of conduct and electoral law.
image caption"Cummings declares war on Johnson", is the headline on the front page of the i. The paper says Mr Cummings has attacked the prime minister's character, questioning Mr Johnson's "competence and integrity".
image captionThe Guardian says Mr Cummings used a lengthy post on his personal blog to deny any leaking of the prime minister's text messages. Mr Johnson had behaved in a way he considered "mad and totally unethical", the paper says. The Guardian also features news that 39 postal staff who were wrongly accused of theft and fraud have been cleared after a huge miscarriage of justice.
image captionMr Cummings says he has WhatsApp messages, emails and documents to support his claims and he would be prepared to hand them over to a parliamentary inquiry, the Times says. A No 10 source is quoting by the paper as saying the prime minister was "saddened about what Dom is doing" and said the former Downing Street adviser was "bitter about what's happened since he left" in November.
image captionThe Daily Telegraph leads on the "war" between Mr Cummings and Mr Johnson. But its front page also carries a message from government scientists who say face masks may not be needed this summer as the vaccine does the "heavy lifting" in the battle against coronavirus. However, it says some experts have called for masks to remain in place to prevent a new surge of infections.
image caption"Smile! No masks by the summer", is the headline on the Daily Express, which also reports that face masks could be ditched this summer. The paper quotes a senior source as saying there is nothing in the data to throw off course plans to remove social contact limits in England on 21 June.
image captionThe Daily Star says a Great White Shark is heading to Britain. Its front page picture features of mock-up of Boris Johnson as a swimmer and Dominic Cummings as a diver alongside a shark.