LONDON -- Oil prices fell during the first part of this week before regaining lost ground following European Central Bank President Mario Draghi's comments that the ECB would do whatever was necessary to support the euro. Shortly after U.S. markets opened on Friday, the United States Oil Fund (NYSE: USO) was up by 1.5% while the United States Natural Gas Fund (NYSE: UNG) was down by just 0.2% on the week.

Despite a broadly stable oil and gas market, some junior oil and gas shares managed to outperform the prices of oil and gas by a wide margin. Here are three of this week's top climbers:

Mediterranean Oil & Gas
Mediterranean Oil & Gas topped this week's risers, gaining 28% to 12.7 pence. The main driver behind the gains is the news that the decree lifting the ban on offshore drilling in Italian waters has been ratified by the Italian parliament. As a result, Mediterranean is hoping to be able to start production from its Ombrina Mare oil and gas field in the Adriatic -- its operations in Italian waters have been suspended since the ban on offshore drilling started in 2009.

Lansdowne Oil & Gas
Lansdowne Oil & Gas rose 6.6% this week to 64.8 pence, following an upgrade of the P50 mean oil-in-place estimates for Barryroe, a field in the Irish Sea, from 373 million barrels to 1,043 million barrels. Barryroe operator Providence Resources is now expected to begin looking for a farm-in partner to help fund development of the field and will provide an updated competent person's report for Barryroe by the end of the year.

Faroe Petroleum
Faroe Petroleum (LSE: FPM.L) climbed 6.5% to 148 pence this week following a positive update from its Cooper well and news that it has doubled its bank lending facility from $125 million to $250 million. Faroe is now performing a drill stem test on the Cooper well, which should provide investors with more definite information about the likely productivity of the well.

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