Glencore Xstrata to appoint female director by year-end

* Group is only FTSE 100 company with all-male board

* Issue has drawn criticism from shareholders

* Female representation on FTSE 100 boards now up to 20 pct

* Single Glencore appointment not enough, says fund adviser

By Silvia Antonioli

LONDON, May 20 (Reuters) – Glencore Xstrata plans to appoint a female board member by the end of the year, its chairman told shareholders on Tuesday, and rid itself of the dubious distinction of being the only British blue-chip company with an all-male board.

The mining and commodities-trading group and its chairman, Tony Hayward, have come under fire from some investors over its apparent failure to embrace the recommendations of a 2011 government report into the lack of diversity at the top of Britain's leading companies.

The British government's 2011 Davies Review set a target for all companies in the FTSE 100 index to have a quarter of their board positions held by women by 2015, stating that "inclusive and diverse boards are more likely to be effective boards, better able to understand their customers and stakeholders and to benefit from fresh perspectives, new ideas, vigorous challenge and broad experience".

Though the review stopped short of advocating enforced quotas, the percentage of women board members at FTSE 100 companies had risen to 20.7 percent by March this year, from 12.5 percent in 2011.

When Chilean mining company Antofagasta appointed Vivianne Blanlot as a director in March, that left Glencore as the only FTSE 100 company without female representation on its board.

UNIMPRESSED

But that will change by the end of the year, Hayward told the company's annual general meeting on Tuesday.

"Glencore values and promotes diversity across its business. The appointment of a female board member would be a key sign of that commitment to this area," said Hayward, the former BP boss who was appointed as permanent chairman this month after a year as interim chairman.

"It's an important priority of the board to appoint a female director before the end of this year."

But his comments received a less than enthusiastic response in some quarters.

"If Glencore were to appoint a single woman on the board by the end of the year, that would still leave them as the laggard of the FTSE 100. The question of diversity has gone past one representative on the board," said a spokesman for London-based fund adviser Pensions Investment Research Consultants (PIRC).

"Glencore should foreshadow to the market now what the 2015 targets are for board diversity, and they need to get a bit of a hurry up."

(Editing by David Goodman)