The Queen approved Boris Johnson’s request to suspend Parliament no earlier than Spetember 9 and no later than September 12, until October 14.
Mr O’Mara, who has endured a turbulent two years in office, has formally notified the Government he intends to resign when MPs return after their summer recess on Tuesday.
Dr Felicity Matthews, a senior politics lecturer at Sheffield University, said if the Queen approves the Government’s request it could shorten the amount of time for the troubled MP’s planned resignation to be dealt with.
She said: “The Government can’t do anything until Parliament is sitting because the Speaker has to issue a writ. Parliament is still resuming on September 3 so, in theory, his resignation should not affected.
“But if there is a General Election, that might affect the timing of a by-election because it could be tied in with that.
“I can’t see why it wouldn’t be dealt with next week unless Parliament changes the dates of the suspension.”
Mr O’Mara was reportedly arrested on suspicion of fraud earlier this month, alongside his chief of staff Gareth Arnold, who, it is alleged, was arrested on suspicion of conspiracy to commit fraud.
Both men were released pending further investigation.
The Treasury confirmed it had received a ‘short contact’ from Mr O’Mara confirming his intention to resign.
Dr Matthews said MPs cannot directly resign their seat and instead they apply to be appointed to two historic ‘offices’ – the Crown Steward and Baliff of the Manor of Northstead – with the chancellor, currently Savid Javid, issuing the writ.
By law, taking on one of these titles immediately bars a person from being an MP.
The lecturer added: “There was always a relatively short period of opportunity for this to happen because even without the suspension, Parliament was always going to be suspended during for the party conferences in late September anyway.”
Meanwhile, Sheffield Central MP Paul Blomfield; Louise Haigh, the Sheffield Heeley MP; Clive Betts, MP for Sheffield South East and Angela Smith, MP for Penistone and Stocksbridge, have all signed the Church House Declaration, against the Government's plans.
The politicians are among more than 200 MPs from across the country and political parties who have pledged to work cross-party and cross-nation to prevent the country 'driving through a no deal Brexit'.
Mr Blomfield said: “Suspending Parliament to prevent MPs influencing the biggest decision in our post-war history is treating our democracy with contempt and makes a mockery of the Brexiteers’ claim to champion parliamentary sovereignty.
“I will work with the other Church House Declaration signatories to use every political and parliamentary tool at our disposal to prevent Boris Johnson trashing our democracy and crashing out of the EU without a deal, which would be disastrous for the livelihoods and security of our people.”
Mr Blomfield, Ms Haigh and prospective Labour party candidate for Sheffield Hallam Olivia Blake will hold a rally outside Sheffield Town Hall at 11am on Saturday and invited ‘everyone from any or no party who opposes Boris Johnson’s attempt to shut down Parliament’ to join them.
Boris Johnson said a Queen’s Speech would take place after the suspension, on 14 October, to outline his ‘very exciting agenda’.