The Department of Enterprise, Trade and Employment considered 15 per cent more mergers in 2002 than in the previous year, according to Government figures.
The increase in the Department's workload came as it prepared to relinquish responsibility for mergers to the Competition Authority at the start of this year.
The Tánaiste, Ms Harney's Department considered a total of 99 mergers last year, compared to 86 in 2001.
The Competition Authority has said that it expects to assess about 40 mergers each year under rules unveiled last week.
The new system, which places onerous notification requirements on merging parties, applies only to companies with a global turnover of more than €40 million. In addition, at least one merging company must have a turnover of €40 million or more in the Republic.
The authority expects the height of these thresholds to reduce the number of mergers coming under its ambit. As of last week, no mergers had yet been notified to the Competition Authority.
Anecdotal evidence suggests that the growth in merger notifications last year may have been influenced by a preference among legal practitioners to deal with a familiar regime before it fell into extinction. The busiest sector for mergers activity in 2002 was financial services, which accounted for about 18 per cent of all notifications.
Media mergers, which have remained under the ultimate aegis of the Tánaiste under the new system, accounted for 8 per cent of last year's total.
The most pronounced difference between notification records for 2001 and those of 2002 came in the troubled information technology (IT) sector.
IT companies were the source of 16 merger notifications in 2001, but this fell to four last year in line with the general technology downturn.