Women struggling to crack glass ceiling in top UK companies-report

* Women hold fifth of board positions in FTSE 100

* Government report author says eyes of world on Britain

* Report feeds into debate about quotas

By Belinda Goldsmith

LONDON, March 26 (Reuters) - More women are sitting on theboards of Britain's biggest companies but the glass ceiling isyet to crack, with most top jobs still held by men and companiesneeding to do more for gender balance, a report showed onWednesday.

The latest of three British government reports on gender inboardrooms found women now hold a fifth, or 20.7 percent, ofboard positions in FTSE 100 companies, up from 17.3 percent inApril 2013 and 12.5 percent in 2011, but short of a 2015 target.

The figures showed women accounted for 6.9 percent ofexecutive directorships in the FTSE 100 while making up 25.5percent of non-executive directorships and their representationon FTSE 250 company boards fell to 15.6 percent.

The report by former trade minister Mervyn Davies comesduring a debate in many countries and the European Union aboutthe pros and cons of mandatory quotas to boost women numbers atthe top. Critics argue that quotas lead to "trophy directors".

Davies, who left his role as Standard Chartered chief executive in 2009 to enter government, oversaw a reviewinto the lack of women board members in 2011 and set a target tohave women in one quarter of British boardroom seats by 2015.

"The rate of change that we have seen at the heart of ourbiggest companies over the last three years has beenimpressive," said Davies.

"However, the eyes of the world are on us as we enter thehome straight. They are judging us as to whether the voluntaryapproach, rather than regulation, will work - we need to nowprove we can do this on our own."

QUOTES OR VOLUNTARY?

While countries such as Norway, the Netherlands, and France have introduced mandatory quotas, Britain and Germany haveresisted such moves.

Davies, who returned to the City after the 2010 nationalelection and sits on several boards himself, stopped short ofmandatory quotas and recommended FTSE 350 companies set theirown targets instead which was welcomed in the corporate world.

Several British banks released targets on gender balance intheir annual results for the first time this year.

HSBC is aiming to have women in 25 percent ofsenior roles by 2014/15, up from 22.7 percent; Lloyds has a target of 40 percent by 2020 compared to 28 percent now;and Barclays is eyeing 26 percent by 2018, up 5 pointsfrom now.

Despite the voluntary drive, Britain still lags somecountries on female presence with only four FTSE 100 companieshaving female chief executive.

Two FTSE 100 firms, Glencore Xstrata andAntofagasta, have no women in the boardroom - althoughboth told Reuters they were looking for suitable women boardmembers - and there are 48 all-male boards among FTSE 250companies.

Audrey Williams, partner at global law firm Eversheds, saidmore could be done to drive up women numbers at top levelswithout using quotas such as sponsoring and mentoring women.

"There is a fear that quotas lead to tokenism and women arenot appointed on merit but the Davies reports have acted as akind of catalyst and given organisations more strength of voiceto push forward the agenda," she told Reuters. (Additional reporting by Steve Slater, Editing by AlisonWilliams)