The Tories said the PM may have broken the MPs' code of conduct by failing to declare past support from the Labour Together think-tank, previously run by his chief of staff (pictured with Sir Keir).

The Tories say they have obtained private legal advice to Morgan McSweeney (pictured), which points to a deliberate attempt to mislead the Electoral Commission.

The Tories said the PM may have broken the MPs' code of conduct by failing to declare past support from the Labour Together think-tank, previously run by his chief of staff…