By James Mackenzie
ROME (Reuters) - Italian Prime Minister Matteo Renzi's ruling centre-left party promised on Monday to push on with its reform agenda after anti-establishment and euro-sceptic parties posted strong results in local elections.
Centre-left candidates backed by Renzi's Democratic Party (PD) won five out of seven regions that voted on Sunday. But a fall in the overall vote and the loss of the key region of Liguria dented the unchallenged supremacy Renzi, 40, has held over Italian politics since becoming prime minister in Feb 2014.
PD officials said the results, which still leave the party in control of 17 of Italy's 20 regional governments, showed clear support for Renzi's agenda. But they could not hide their dismay at losing Liguria, in part due to a breakaway leftist candidate who split the leftwing vote.
"Obviously the result in Liguria is bitter for us," said PD deputy secretary Debora Serracchiani. She said the overall result vindicated the government's pledges to change Italy's labor laws, judicial system and public administration in order to reawaken Italy's lethargic economy.
The anti-immigrant Northern League, which wants to scrap the euro, benefited from public concern over refugee arrivals in southern Italy to score a decisive win in the northeastern Veneto region. It also expanded outside of its main heartlands.
Together with a strong showing for the anti-establishment 5-Star Movement, the result confirmed the appeal of anti-system parties in the euro zone's third-largest economy after years of recession and Brussels-inspired austerity.
"HARDER FOR RENZI TO GOVERN"
For the PD, the result is a sharp fall from a record 41 percent that Renzi gained in last year's European elections after he rose to power in an internal party coup.
The regional elections have no direct impact on national politics but Renzi needed a convincing result to maintain momentum for labor, education and constitutional reforms which have met fierce resistance from trade unions, the political opposition and the left wing of the PD.
"From now on, it will be harder for Renzi to govern," said the daily La Stampa in a front page editorial.
A low turnout of just 54 percent also demonstrated a mood of disillusion among many voters after a campaign dominated by corruption scandals and internal party squabbling.
Renzi, who left Italy unexpectedly on Monday for a short visit to Italian troops serving in Afghanistan, has so far made no comment on the election. His only reaction was a picture tweeted late on Sunday night showing him playing a videogame with a senior PD official as they waited for the results of the election to come in.
Matteo Salvini, the Northern League's 42-year-old leader, emerged as one of the strongest winners. A blunt speaker who recently posed bare-chested in bed for an Italian magazine, Salvini has become the leading figure of Italy's right.
His popularity is eclipsing that of the 78-year-old ex-Prime Minister Silvio Berlusconi who has struggled to hold his Forza Italia party together.
On Monday, Salvini said he was already looking ahead to national elections due in 2018.
"I am ready to challenge Renzi tomorrow morning. Voters who choose the League are choosing a movement with courage which I think will govern Italy," he told Canale 5 television.
(Reporting by James Mackenzie; Editing by Peter Graff)