The Government has already published guidance informing business of steps to take in the event of No Deal. This includes guidance on rules of origin and will be updated as required.
For trade with countries where no trade agreement is in place between the UK and those countries, non-preferential rules of origin will apply.
For trade with countries where we have a signed trade agreement in place, the rules of origin that apply can be found in the text of the agreements. These are published online, and the full text, Explanatory Memoranda and Parliamentary Reports for these agreements are laid in the libraries of both Houses.