The campaign to reduce the physical distancing rule from two metres to one has received a setback after an influential study concluded that the wider the gap, the lower the risk of infection.
Distancing of at least one metre lowers the risk of Covid-19 transmission - but two metres is more effective, the study in The Lancet reveals.
It comes as just one person was reported to have been killed by the virus in the Republic of Ireland yesterday - the second lowest daily death toll since late March.
However, another 77 new cases of the virus were diagnosed, signalling that it continues to pose a risk.
There was also mounting concern at the breaching of safeguards over the weekend following student house parties in Cork, which infectious disease experts fear can be a breeding ground for the virus.
It led to residents living near University College Cork staging a silent protest at the parties by students who have rented houses nearby.
As the country basked in glorious sunshine over the bank holiday weekend, gardai also had to ask groups of sun seekers at the Forty Foot swimming spot in Sandycove, Dublin, to disperse.
Fears about lack of physical distancing also led to beaches in Donegal, Kerry, Cork and Louth being closed to the public.
Dr Sam McConkey, an infectious disease consultant in Beaumont Hospital, warned that house parties increased the risks of the virus being passed on.
The Lancet report, which was part-funded by the World Health Organisation, is the first to look at 172 observational studies on how physical distancing, face masks and eye protection affect the spread of Covid-19 across 16 countries.
It found that analysis of data from nine studies looked at physical distance and virus transmission.
They showed that keeping a distance of over one metre from other people was associated with a much lower risk of infection compared with less than one metre.
The risk of infection when individuals stand more than a metre away from the infected individual was 3pc, versus 13pc if within a metre.
However, the modelling suggests for every extra metre further away up to three metres, the risk of infection or transmission may halve.
Prof Holger Schünemann, from McMaster University in Canada, who co-led the research, said: "Our findings are the first to synthesise all direct information on Covid-19, Sars and Mers, and provide the currently best available evidence on the optimum use of these common and simple interventions to help 'flatten the curve' and inform pandemic response efforts in the community.
"Keeping at least one metre from other people as well as wearing face coverings and eye protection, in and outside of healthcare settings, could be the best way to reduce the chance of viral infection or transmission of Covid-19."
Chief Medical Officer Dr Tony Holohan said: "We now have had more than 25,000 cases of Covid-19 in Ireland and while 90pc of patients have recovered, more than 3,285 people have been hospitalised and sadly 1,650 have died.
"It is vital that we continue to practise hand and cough hygiene and social distancing, with the additional hygiene measure of face coverings in appropriate settings.
"It is important to give space to our vulnerable people when out and about.
"We must continue to do all we can to interrupt the spread of this virus."
Sinn Fein TD for Meath East, Darren O'Rourke, will today question witnesses at the Special Covid Committee as to whether a traffic-light system for travel can be introduced here as a means of safely opening up foreign travel.
Deputy O'Rourke and his party colleague, Sinn Fein Finance spokesperson Pearse Doherty, will also question why the Public Health Passenger Locator Form was only made mandatory last week and how long the 14-day quarantine procedure will be in place.
They say thousands of people are unsure if it is safe to plan for summer holidays abroad, given recent conflicting public messages, and want guidance and reassurance.
"The Government's actions to date on the transport aspect of the Covid-19 crisis have left a lot to be desired," he said.