Lib Dems plan "Cupid clause" bill on Valentine's Day designed to block increase in income requirements.
Ed Davey launches New Year bid to "get rid of as many Conservative MPs as possible".
Ministers have been accused of "neglecting public services at the expense of the British public".
The Tories' 25,000 majority in Mid Bedfordshire was toppled in a huge blow for Rishi Sunak.
The party is defending two safe seats - but Labour and the Lib Dems are aiming to pile more misery on Rishi Sunak.
The two parties are "knocking lumps out of each other" as they try to beat the Tories.
Party leader says voters are "desperate" to see the back of Rishi Sunak's government.
The party will announce the proposal on Sunday at its annual conference.
Lib Dems warn of "a disaster waiting to happen" in the NHS.
A vicious war of words has erupted between the opposition parties - and Rishi Sunak could be the main beneficiary.
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