Update 11.45am: Teams of experienced counters from Cork's City and County Halls have been drafted in to speed up the recount in Ireland South.
It had been expected that the recount, which had been ordered after just 326 votes separated Green party senator Grace O'Sullivan from Sinn Féin's Liadh Ní Riada, would take around 28 working days at a cost of €1m.
The recount in the 12-county constituency began this morning in Nemo Rangers GAA club but it is now expected that the painstaking process of checking every single vote again will be much quicker than expected.
Returning officer Martin Harvey has recruited between 130 and 140 counters and 20 top table supervisors who have experience in the proportional representation (PR) system.
He said these staff have been drafted in from both County Hall and City Hall.
Explaining the process, Mr Harvey said: "At the moment each of the counters has 1,000 votes in front of them, the bands of those 1,000 keeping them together have been cut and each counter is now counting those individually to make sure that the vote credited to the candidate is correct."
Counters are firstly going through the papers of Ms Ní Riada and Ms O'Sullivan and this is expected to take much of the day.
"It is going quite well now, we have a good team around us and hopefully we would finalise that later this evening," said Mr Harvey.
"We go though each and every one of the papers slowly and surely, then make sure the band of 50 is correct, that it tots 50 and then we make sure we have 20 bands of 50 to make up the 1,000 [in each bundle]."
Speaking on RTÉ's Sean O'Rourke show, he added that a yellow sticker will be put on each ballot that requires further analysis and they will be reviewed.
Mr Harvey said Ms Ní Riada, who has called the recount, does have the right to call it off at any stage.
Earlier: Ireland South recount could be resolved in just five days
By Kevin O'Neill
The recount of the Ireland South European Parliament votes could be resolved by the end of the week, according to returning officer Martin Harvey.
Initial reports had suggested that the process could take as long as 28 working days but Mr Harvey has managed to secure a significant increase in the number of staff taking part in the recount process.
Some 130 people are counting the votes at Nemo Rangers GAA club this morning.
While last week's count involved approximately 250 staff, this number had expected to drop below 100 for this week's recount as many staff took annual leave to take part in last week's count.
However, Mr Harvey confirmed that staff from City Hall, County Hall and the Courts Service have been given additional leave to take part in the process.
Staff are expected to count from 9am to 5pm each day this week, with Mr Harvey hopeful that the process could be resolved by Friday or Saturday.
Mr Harvey also said that if the process is resolved in just a few days that the cost will be "significantly less" than the €1m figure reported over the weekend, though he declined to give a specific figure until the process is entirely resolved.
The 755,987 ballots have remained under Garda supervision at Nemo since counting stopped last Thursday.
The recount was called by Sinn Féin after the distribution of Billy Kelleher's surplus put Green Party candidate Grace O'Sullivan ahead by 327 votes, potentially costing Liadh Ní Riada her seat.
A recheck of votes on Thursday gave Ms Ní Riada just one extra vote. Sinn Féin members have said they will call a halt to the recount if it appears that it won't make a difference.