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Dec 29 (Reuters) - Saudi Arabia's finance ministry has increased its stake in the country's biggest construction firm Binladin International Holding Group to 86.38%, state television reported on Monday, describing it as a debt-conversion deal.

The finance ministry and Binladin were not immediately available for comment.

State television did not disclose financial details or say by how much the stake was being raised. Previous media reports have said the state owned 36%.

The country's National Debt Management Center arranged a syndicated loan of about 23.3 billion riyals ($6.21 billion) in October last year to allow the finance ministry to support Binladin as the construction industry is central to Saudi Arabia's efforts to bolster tourism and reduce its dependence on oil revenues.

The conglomerate faced financial challenges because of stalled projects and delayed payments caused by a fall in international oil prices LCOc1.

Binladin Group was also temporarily excluded from new state contracts after a crane accident killed 107 people at Mecca's Grand Mosque in 2015.

($1 = 3.7506 riyals)

(Reporting by Nayera Abdallah, Ahmed Elimam and Utkarsh ShettiEditing by David Goodman and Barbara Lewis)

((Nayera.Abdallah@thomsonreuters.com;))