BUZZ-Oil slide, potential Scottish passenger duty cuts lift airlines

** EasyJet (Other OTC: ESYJY - news) , IAG extend gains as Scotland likely to slash taxes on passengers flying out of the country from next year.

** Slide in oil prices to lowest levels since August 2010 after OPEC resists cutting production provides further boost.

** Easyjet, up 4.9 pct, IAG up 4.4 pct, top gainers on the FTSE. However, gains come on relatively lighter volumes that are in line with the market average.

** Scottish Parliament was on Thursday promised new powers by the UK government, including control over air passenger duty (APD). That would allow the majority Scottish National Party (SNP) to fulfill its pledge to cut or even scrap the tax in Scotland.

** IAG and British Airways fly from a number of Scottish airports, including Edinburgh, Aberdeen and Glasgow.

** Numis Securities analyst Wyn Ellis says tax has been "clearly damaging" for both airlines and, while most of any tax reduction will be passed on to passengers, the move would be positive as it would stimulate travel. (RM (LSE: RM.L - news) : francesco.canepa.thomsonreuters.com@reuters.net; RM: alistair.smout.thomsonreuters.com@reuters.net)