By Liam Moloney

ROME--Italy's unemployment rate rose slightly in September, while the youth jobless rate fell from the previous month, national statistics institute Istat reported Friday, citing preliminary seasonally adjusted data.

The official jobless rate increased to 12.6% in September from 12.5% the previous month, Istat said. It rose also 0.1 percentage point from September 2013.

The youth unemployment rate for those aged 15 to 24, a politically sensitive subject, fell to 42.9% on the month.

The September rate represented a 0.8 percentage point drop on the month and a 1.9 percentage-point rise on the year, Istat said.

"The youth unemployment rate is still hovering at very high levels, above 40% for the past year or so," an Istat official said.

Taming Italy's high unemployment rate, especially youth unemployment, is among the priorities of Prime Minister Matteo Renzi's government as household spending remains weak and families are concerned over possible job losses. The government expects Italy to post in 2014 its third straight economic contraction.

An Istat official noted that there was a drop in inactivity among those aged between 15 and 64 years, "which could be a positive signal as it means seeking greater participation in the workforce."

Italy's employment rate, the percentage of working-age adults with jobs, advanced to 55.9% from 55.4% a year earlier, while the jobless ranks grew by 1.8% to 3.24 million, Istat said.

"For the first time in months, September is the first one with a positive signal for the employment rate which kept staying at around 55.5%," an official said.

Write to Liam Moloney at liam.moloney@wsj.com