Ian Blackford has written to Boris Johnson demanding he acts to recall parliament following the judgement of Scotland's Court of Session which ruled that his advice to the Queen and the suspending of parliament was 'unlawful'.
The SNP's Westminster leader added that the prorogation is "null and of no effect", and that parliament has important matters to discuss this week, including the review of the Prime Minister's Operation Yellowhammer no-deal Brexit planning documents.
The letter further reads: "Every day that Parliament remains suspended, you and the UK Government are shutting down democracy. The UK Government and your office of Prime Minister are not above the law. We must all abide by the rule of law."
Mr Blackford noted that the UK Government was intending to appeal the case next week, but that the Prime Minister should not obstruct the parliament from sitting until the outcome of that hearing.
First Minister Nicola Sturgeon also reacted to today's judgement, saying: "Parliament must be recalled immediately to allow the essential work of scrutiny to continue."