Most North Sea oil output "in the money", but decom bill looms - Woodmac

* First North Sea fields have already been shut

* North Sea operators face huge decommissioning bill

* Halted development spend will lead to stranded assets

LONDON, March 23 (Reuters) - Most North Sea oil and gas
fields can make money at $30 a barrel, but stakeholders in the
fields that have to be shut in the current price rout are set to
face a huge bill for removing facilities like platforms and
subsea infrastructure, Wood Mackenzie said.

The North Sea between Britain and Norway, home of the Brent
crude stream that underpins global oil prices, is one of the
world's oldest and most expensive oil basins.

Crude oil prices have posted four straight weeks of losses
and dropped more than 60% since the start of the year.

Oil and gas producers across the globe are slashing budgets.

Last week, Britain's oil and gas sector called on the
government to help it survive, as the oil price crash triggered
the first field shutdowns.

"In the short term, the North Sea can survive. Cost
reductions achieved during the last downturn mean 95% of
onstream production is 'in the money' at $30 a barrel," said
Wood Mackenzie North Sea upstream analyst Neivan Boroujerdi.

"But close to a quarter of fields will run at a loss in this
price environment. The major concern here is not volumes. Early
shut-ins would accelerate $20 billion in decommissioning spend."

If oil and gas companies cannot pay for decommissioning,
taxpayers may ultimately be liable.

With oil service companies, which provide physical assets,
engineering and staffing services to producers, already squeezed
since the last oil price slump in 2016, most savings are likely
to come from cutting future development, rather than current
operations.

"Annual investment in the UK could fall below $1 billion as
early as 2024. The threat of stranded assets is real – we
estimate nearly 6 billion barrels... could be left in the
ground," Woodmac said.
(Reporting by Shadia Nasralla; Editing by Jan Harvey)