The pound to euro exchange rate is currently £1 to €1.15, dropping from €1.16 earlier today.
Concerns have rippled across the market that the UK will be foreced to leave the EU without a deal, weighing on the value of the pound.
A no-deal Brexit scenario is seen by investors as a damaging outcome for the UK economy and therefore the possibility this could come to fruition has caused the rise in the value of the pound to turn to dust.
Mr Johnson is required to obtain an approved Brexit deal by Saturday October 19 or he will be required, by law, to request a deadline extension.
However, it does not appear likely that the EU would grant such an extension.
Earlier today, the EU Commission President Jean-Claude Juncker said: “We have a deal so why should we have a prolongation.”