Newspaper headlines: Tory MP defects and Labour 'would keep triple lock'

The defection of Tory MP Dan Poulter to Labour features in many of Sunday's papers

The defection of Tory MP Dan Poulter to Labour features on a number of Sunday's front pages.

The Observer says discussions between Mr Poulter and senior Labour figures have been going on for many months, but only half a dozen people knew about what was planned. Writing in the paper, Mr Poulter says he will not stand at the next general election, but that he envisages a role advising Labour on its policies on mental health, while focusing more on his work as an NHS doctor.

According to the Sunday Telegraph, a group of Tory MPs are hoping the defection will help them persuade colleagues to oust Prime Minister Rishi Sunak and unite around the leader of the Commons, Penny Mordaunt, as his successor. The paper says the rebels want to remove Mr Sunak and announce a wave of new policies - including tax cuts and pledges on immigration and the NHS - before the next general election is called. They argue that otherwise the party faces "an extinction level event" at the election.

Ms Mordaunt has distanced herself from the plotters. She told the Sunday Times that MPs should stop engaging in "Westminster gymnastics".

The Sun says Mr Sunak could face a leadership challenge within days of the local elections in England and Wales on Thursday if the Tories suffer a bloodbath at the polls. The paper says the party could lose between 400 and 500 councillors and its two most popular mayors, Ben Houchen and Andy Street. The Sunday Mirror says Mr Street has scrubbed references to the party from his website.

In an interview for the Sunday Express, the prime minister urges voters to stick with his plan. He declared himself the man to give people "peace of mind" and unlock a "brighter future".

The Sunday Times reports that Conservative MPs were warned by party whips not to back calls for immediate compensation for the victims of the contaminated blood scandal, because it would mean the chancellor couldn't afford to cut taxes in last month's budget. The paper says Treasury estimates are that the compensation payments could cost up to £22bn.

The prime minister suffered a Commons defeat on speeding up payments - and Jeremy Hunt went on to cut 2p from national insurance anyway. A No 10 source said the threat was not something they were aware of.

Writing in the Sunday Express, Labour leader Sir Keir Starmer promises to protect the pensions triple lock if he becomes prime minister. That's the guarantee that state pensions will rise in line with inflation, average wage increases, or by 2.5%, which ever is highest.

The paper says the pledge is a sign of a fierce battle for the support of older voters, as over 75s are the only age group in which more people support the Conservatives than Labour.

Under the headline "Despicable", the Sunday Mirror says people smugglers in France are hiding migrants in former Nazi bunkers before loading them onto dinghies for the perilous voyage to the UK. The paper's reporter says he saw dozens of desperate Kurds herded into the concrete relics.

And finally the Sunday Times says a new book about Anthony Blunt - a member of the Cambridge Five spy ring, who worked for the Soviet Union - suggests that he also passed secrets to the Nazis during the Second World War. Blunt is described as the most likely candidate to be a spy code-named "Josephine" who told the Germans about the Allied plan to send thousands of paratroopers into the occupied Netherlands in September 1944.

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