UPDATE 1-S.Africa's Eskom flags maintenance backlog amid severe outages

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June 29 (Reuters) - South African state power company Eskom said on Wednesday that there was still a high level of absenteeism among its workforce due to a strike and that it could take weeks to clear a maintenance backlog.

Eskom added in a statement that as previously communicated it would resume so-called 'Stage 6' power cuts from 1600 until 2200 local time (1400 until 2000 GMT) on Wednesday, a level of outages only previously seen in December 2019 before this week.

Stage 6 power cuts, which were also implemented on Tuesday, mean at least six hours of power cuts a day for most South Africans.

"As a result of the unlawful strike, routine maintenance work has had to be postponed. This backlog will take days to weeks to clear," Eskom said.

"It is therefore important to note that the system will remain constrained and vulnerable to additional breakdowns while recovery activities are in progress."

Wage talks between Eskom and trade unions reached a deadlock last week, after which some workers started striking despite a court interdict blocking them from doing so.

Public Enterprises Minister Pravin Gordhan said on Tuesday that Eskom and unions had agreed a wage settlement at a meeting on Tuesday that they would commit to later, but Eskom's two biggest unions later denied an agreement had been reached.

The National Union of Mineworkers and National Union of Metalworkers of South Africa said a new salary offer from Eskom still needed to be discussed with union members and at a bargaining forum on Friday. (Reporting by Anait Miridzhanian in Gdansk and Bhargav Acharya in Bengaluru; Writing by Nellie Peyton in Dakar; Editing by Alexander Winning)