Labour MPs warned to tow the party line or risk economic instability

The briefings are being given to MPs and special advisers by former Treasury minister Kitty Ussher and former shadow minister Gregg McClymont.

They are warning that the biggest threat to the gilt markets is political instability, especially within the Labour party.

Ussher, who works for Barclays and has been invited to give these talks by No10, is telling politicians that the failure to get fiscal priorities through Parliament is worrying the markets, especially the Government’s failure to get their intended welfare reforms through Parliament in July.

LBC also understands that in one of these meetings attendees were told that 'chaos could be unleashed' in the markets if the Chancellor Rachel Reeves was replaced in No11.

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When asked what the point of these meetings were, one attendee said: “to scare people into submission ahead of the Budget”.

An MP told LBC that they were intended to “talk through the economic realities of what’s faced by the Government, what the trade offs are, and what the implications are. So people have a solid grounding in why the fiscal rules are so important, why we can’t just spend loads and not tax.”

Downing Street has been approached for comment.