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Ukraine appoints former minister to head Naftogaz

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Previous chief executive quit this week

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Naftogaz stuck in default, made net loss in first half

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Many Ukrainian energy facilities hit by Russian missiles

KYIV/LONDON, Nov 4 (Reuters) - The new chief executive of Ukrainian state energy company Naftogaz promised on Friday to boost international investors' confidence in the firm and provide energy security, despite the war with Russia.

Oleksiy Chernyshov, 45, was appointed by a government order signed by Prime Minister Denys Shmyhal on Thursday and replaced Yuriy Vitrenko, who quit without giving a reason after less than two years in the role.

Chernyshov, until now the communities and territorial development minister, faces challenges including Russian missile strikes on energy infrastructure, a company debt problem and a dispute with Russian gas company Gazprom.

"We have a lot of work to do for Naftogaz to become a strong, independent, transparent institution capable of effectively fulfilling the tasks before it," Naftogaz quoted Chernyshov as telling staff after being introduced by Shmyhal.

It said Chernyshov set out priorities including "ensuring energy stability and independence; growing confidence in Naftogaz from the state, international partners, creditors and investors; stable passage of the current heating season."

Naftogaz is Ukraine's largest national oil and gas company and its subsidiary, Ukrtransgaz, operates a pipeline system that carries Russian gas to Europe.

Naftogaz is locked in an arbitration battle with Gazprom, saying the Russian energy giant has not paid transit fees for sending its gas to Europe.

The company, which accounted for almost 17% of Ukraine's budget revenue last year, is also stuck in default after bondholders of two of its three main international bonds refused to sign up to a debt payment deferral plan offered this year.

Vitrenko's position became untenable after the government openly criticised Naftogaz's handling of the debt problems.

A source close to bondholders that rejected a debt deferral proposal made by Naftogaz in August said there was hope that Chernyshov's appointment and the likely appointment of new advisers would break the deadlock - financial advisory company Lazard is tipped to take on the role.

"Hopefully that will inject some urgency into the process," the source said, disappointed that there had been "zero engagement" from the firm or government since the spurned deal.

FINANCIAL LOSSES

Naftogaz's announcement on Thursday of a net loss of 57.16 billion hryvnias ($1.57 billion) in the first half of this year highlighted the difficulties the company faces following Russia's Feb. 24 invasion.

On its default, it said on Thursday it continues to develop new terms for the restructuring of its bonds, and intends to start a new consent solicitation process in the near future. The holders of one its main bonds did agree to its August proposal but those owning its two others did not.

The final terms to be offered to bondholders are to be approved by the government, it added.

"There is no secret to where we are, we are not hiding anywhere," said the source close to bondholders. "We know this is an existential situation, but we think there is a constructive conversation to be had."

(Reporting by Max Hunder in Kyiv and Marc Jones in London Additional reporting by Anna Pruchnicka in Gdansk Writing by Timothy Heritage Editing by David Evans and Matthew Lewis)