The move was aimed at reducing the group's estimated dollars 1bn debt mountain and takes proceeds from disposals this year to more than dollars 1.5bn.
Yesterday's deals included the sale of an 8.52 per cent interest in the North Sea T-blocs to Murphy Oil, the US group, for dollars 100m. Lasmo is raising another pounds 15.2m from the disposal of two other blocks to Enterprise Oil, the UK independent.
It is also selling a 3.72 per cent interest in a production-sharing agreement in Sumatra to a Japanese buyer for dollars 19.5m.
The deals bring the total amount raised from Lasmo's exploration and production assets to about dollars 400m this year.
Another dollars 1.1bn came from refining and retailing interests, following the pounds 1bn contested takeover of Ultramar last December.
The company said it was planning further disposals next year. Analysts believe these could involve other North Sea blocks in which Lasmo has a small interest.
Chris Greentree, chief executive, said: 'Since acquiring Ultramar, we have achieved our stated objective of disposing of Ultramar's major downstream assets and exceeded our 1992 upstream disposal target.'
However, Lasmo's shares have fallen from 265p to a 12-month low of about 115p since Ultramar's takeover.
There are fears that the group's high debts may force it to cut this year's dividend.
The company is understood to be considering an ADR listing in New York next spring to attract more US investors.Reuse content