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Boris Johnson did not rule out shutting down Parliament again if the Supreme Court finds his current prorogation was unlawful.

Speaking to reporters after the conclusion of the third day in court, Johnson demurred when he was asked to rule out a second prorogation. "I have the greatest respect for the judiciary in this country," he responded, according to the Press Association.

"The best thing I can say at the moment whilst their deliberations are continuing is that obviously I agree very much with the Master of the Rolls and the Lord Chief Justice and others who found in our favour the other day," he added.

"I will wait to see what transpires."

The suggestion that Johnson could order a second prorogation was raised in the government's submission to the court, which said that "depending on the court’s reasoning it would still either be open or not open to the prime minister to consider a further prorogation" for the same period of time.

On the state of his Brexit negotiations with the EU, Johnson said: "I don't want to exaggerate the progress that we are making, but we are making progress.

"We need to find a way whereby the UK can come out of the EU and really be able to do things differently, not remain under the control of the EU in terms of laws and trade policy, this is the problem with the current agreement," he added, while also saying that the UK will continue to "get ready" for a no-deal Brexit.