Hungarian opposition leader pledges to unlock EU funds if elected

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Some opinion polls show Orban's Fidesz trailing opposition challenger

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Hungary's economy hit by inflation, two years of near-stagnation

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S&P has cut Hungary's rating outlook to negative amid fiscal risks

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Opposition leader plans referendum on Ukraine's EU membership

By Krisztina Fenyo and Gergely Szakacs

BUDAPEST, April 13 (Reuters) - Hungarian opposition leader Peter Magyar vowed on Sunday to unlock billions of euros of suspended European Union funding to revive the economy if elected next year, and to hold a referendum on whether Ukraine should join the 27-member bloc.

Standard & Poor's cut Hungary's credit rating outlook to negative from stable late on Friday amid growing risks to fiscal stability from trade wars, lower EU fund inflows and high debt servicing costs amid budget loosening ahead of a 2026 election.

In power since 2010, right-wing Prime Minister Viktor Orban has been locked in a series of running battles with the EU on rule-of-law reforms, which has led to a suspension of funding, hitting the economy weighed down by years of high inflation.

Some surveys show Magyar's centre-right Tisza Party has overtaken Orban's nationalist Fidesz in opinion polls after two years of near-stagnation and new risks to Hungary's export- reliant economy from U.S. tariffs on imports from the EU.

"Hungary will again be a proud and reliable NATO ally. Hungary will again be a fully-fledged member of the EU," Magyar told supporters after presenting the results of a nationwide survey he said would form the basis of a government agenda.

While Orban's government expects economic growth to accelerate to 2.5% this year, S&P sees a mere 1.5% expansion, which would cap the weakest three-year stretch leading up to a national election during Orban's 15-year rule.

"Unlocking the EU funds alone could boost the economy by at least 1%, which would yield an additional 800 billion forints ($2.22 billion) for the budget," Magyar said, adding that a predictable economic policy would curb debt financing costs.

Assessing the survey's results, Magyar said the issue of Ukraine's EU membership was divisive, therefore he would hold a binding referendum on the issue when the exact conditions of Ukraine's entry emerge.

Orban, who has strongly opposed providing NATO military and EU aid to Ukraine, says the country's EU membership would destroy Hungarian farmers and the wider economy. ($1 = 360.54 forints) (Reporting by Krisztina Fenyo Writing by Gergely Szakacs Editing by David Evans)