* Latest example of M&A deal focusing on N.Sea oil assets
* "Landmark deal" is first valuation of Sverdrup oilfield
* Field may account for 25% of Norway oil, gas output atpeak
OSLO, July 8 (Reuters) - Shares in Lundin Petroleumand Equinor rose on Monday after theNorwegian major cut its stake in the Swedish firm in exchangefor a higher stake in a major oilfield, the latest example of atransaction focusing on North Sea assets.
Shares in Lundin Petroleum were up 3.4% at 0828 GMT, whileEquinor's were up 1.5%, outperforming a European oil and gasindex up 0.35%.
"A landmark deal," said Sparebank 1 Markets in a note toclients, noting it enabled Equinor to secure the gains of itsacquisition of a stake in Lundin in 2016 and was the firsttransaction enabling a valuation of the Sverdrup field.
It is also the latest deal focusing on North Sea oil assets,after DNO's acquisition of Faroe Petroleum in Januaryand Chrysaor's acquisition of ConocoPhillips' Britishoil assets in April, among others.
Under the deal, Equinor would sell a 16% stake in LundinPetroleum for about $1.56 billion, and in return acquire anadditional 2.6% stake in the Johan Sverdrup oilfield for $910million.
Equinor would still retain a 4.9% stake in Lundin and wouldincrease its ownership in the Sverdrup field, which it operates,to 42.6%. The other partners are Aker BP and Total.
Sverdrup, scheduled to start production in November, is thebiggest oil discovery made off Norway in more than three decadesand is likely to account for 25% of the Nordic country's totalpetroleum output at its peak in 2022.
"The transaction is the first ever where one can directlyobserve the Sverdrup value," Sparebank 1 Markets said,suggesting the field's value could be higher than previouslyexpected.
"The value corresponds to $35 billion for the entireSverdrup field, or $11-16 per barrel of oil equivalent (boe),"it said.
"$11/boe is based on the lower end of the resource range of2.2 billion-3.2 billion boe and $16/boe based on the upper endof the resources range. As a comparison, we have valued Sverdrupat $11.9/boe," it said.
Bernstein also has a new valuation of the overall fieldof$35 billion and $10.9-$15.9/boe on current recoverable reserveestimates.
"This is above our field model's net present value of around$26 billion in 2019 and around $32 billion in 2020 at $60 perbarrel, adding further to our bullishness on the field withpotential early start up and recoverable reserve increases," itsaid in a not to clients.
"Indeed, the implied multiple is ahead of the $10.3 per boethat has been paid across more average North Sea transactionsconfirming the quality of this field."(Reporting by Gwladys Fouche, editing by Louise Heavens)