Emirates National Oil plans to delist Dragon Oil from the Irish and London stock exchanges following its acquisition of the company.
ENOC, which already holds a majority stake in Dragon Oil, made an offer to buy the rest of the company in May and recently increased its price to 800p per share.
This values the company at almost £3.95 billion (€5.6 billion).
ENOC said its offer would remain open to shareholders until 3pm on 28 August, however it indicated that it had already received acceptances covering the majority of the outstanding share capital.
Dragon Oil also released its results for the first half of the year this morning, reporting an 18% dip in revenue to $449.9m.
Operating profits were down even more, however, declining 54% to $179.1m.
Chief executive Dr Abdul Jaleel Al Khalifa said the sharp drop in crude oil prices was reflected in these figures and came despite an increase in production by the company.
Dragon Oil said it was now producing more than 100,000 barrels of oil per day, which it plans to be its minimum average until 2021 at the earliest.