(Adds details on discovery, share movements)
April 2 (Reuters) - Premier Oil Plc and Falkland Oiland Gas Ltd said they made an oil and gas discovery ata well in the Falkland Islands, the first in a nine-monthdrilling campaign.
The companies said the discovery of 81 feet of net-oilbearing reservoir and 55 feet of net gas-bearing reservoir atthe Zebedee well was better than expected.
Analysts for brokerage Stifel, however, said the uncertaintyaround the development of the Sea Lion project meant thediscovery was unlikely to change the picture in the NorthFalkland basin.
"A full appreciation of the significance of today's resultmay have to wait until the conclusion of the drilling campaignlater this year."
In November, Premier Oil scaled back its Sea Lion oilfieldproject after struggling to find a partner and weak oil pricesput pressure on the company to cut costs.
Shares of Premier Oil rose as much as 6.5 percent, whilethose of AIM-listed Falkland Oil gained 26.8 percent beforereversing course to fall 17 percent to 29.48 pence in earlytrade on Thursday.
Premier owns 36 percent of Zebedee, while Falkland Oil holds40 percent and Rockhopper Exploration Plc the remaining24 percent.
Rockhopper's shares rose 12.8 percent, before paring gainsto trade up 1.6 percent at 64.64 pence on the London StockExchange.
Drilling for oil and gas in the resource-rich FalklandIslands by London-listed companies remains controversial as adecades-long row between Britain and Argentina over thesovereignty of the islands has not been resolved.
Zebedee is the first of six wells that are part of adrilling campaign started in March by Rockhopper and FalklandOil and involves Premier Oil and Noble Energy Inc.
The companies, which announced the discovery in separatestatements, said the well will be plugged and abandoned as asuccessful exploration well and the rig will be moved to thesouthern part of the North Falkland Basin.
(Reporting by Abhiram Nandakumar in Bengaluru; Editing byAnupama Dwivedi)