* Britain offers 27 onshore oil and gas blocks
* Many EU countries have banned shale gas fracking
* Licence offers follow planning rule changes made last week (Adds details, background, Cuadrilla comment)
By Karolin Schaps and Susanna Twidale
LONDON, Aug 18 (Reuters) - Britain offered shale gasexploration licences for the first time in seven years onTuesday, awarding new sites to companies including IGas and France's GDF Suez.
Prime Minister David Cameron has promised to go "all out forshale", hoping it will help reduce dependence on energy importsand generate additional tax revenue, despite opposition fromenvironmental campaigners.
Many other European countries, including France and Germany,have banned the use of shale gas hydraulic fracturing, orfracking, due to environmental concerns. Britain is estimated tohave decades worth of gas needs underground but so far has noshale gas producing wells.
All of the new licensing blocks are in England asparliaments in Wales and Scotland have imposed moratoriums onfracking due to the public's environmental concerns.
The new licensing round, delayed since the start of theyear, offered 27 new shale gas and conventional explorationblocks and attracted 95 applications from 47 companies, thegovernment said, showing developers are still interested inexploring for the unconventional fuel in Britain.
The government also offered new blocks on Tuesday toexplorers Egdon Resources and Cuadrilla Resources, aswell as Swiss chemicals company INEOS.
"We are keen to move quickly to evaluate the potential ofthis resource, and determine if we can economically produce gasfrom our licenses," said Gary Haywood, chief executive of INEOSShale, in a statement.
The licences, around half of which relate to conventionaloil and gas drilling, will be formally awarded once furtherassessments are carried out on a second tranche of 132 blocksthat could be awarded at a later date.
INEOS has applied for shale gas licences in Scotland as partof a $1 billion investment plan but has so far been unable toproceed due to the moratorium.
However, progress has been slow because of opposition bylocal residents and environmental campaigners. Some areconcerned about groundwater contamination from chemicals used inthe hydraulic fracturing -- or fracking -- process, while othersfear the potential impact on property prices or tourism.
Despite these concerns, the government fully supports shalegas development and Tuesday's licence awards show it intends tocontinue pushing it forward.
Last week, it changed planning guidelines to fast-trackapplications for fracking after local politicians in northwestEngland rejected two Cuadrilla planning permits in June.
Cuadrilla said on Tuesday it would work with the localcommunities in its new licence areas from the start. (additional reporting by Simon Falush, editing by David Evansand William Hardy)