British boardrooms are still too white and ethnic diversity is 20 years behind gender diversity

There are more women than ever before in UK boardrooms, according to a major new report from headhunter Spencer Stuart - but ethnic diversity is still a huge issue.

The Board Index 2015, launched on Monday, the number of women chairing FTSE 150 companies has risen by 5 since 2013, taking the total to 7.

The findings may be broadly positive, but two of the UK's most senior businesswomen were quick to temper any over-enthusiasm.

Speaking to the Financial Times, Manjit Wolstenhome of Provident Financial, said: "Of course it is real progress, but we are certainly not in a position to say 'job done'. We urgently need many more women and black and ethnic minorities at the top if our boards are to reflect the diversity of our workforce and our customers."

The report shows that only 78 directors - around 5% of the total in the FTSE150 - come from Black, Asian, or minority ethnic background. The figure drops as low as 4% when excluding companies based in emerging market nations. What's more, only 1.9% of directors with British citizenship are from BAME backgrounds.

The report suggests that in terms of diversity levels, minorities are roughly 20 years behind women. "In percentage terms, BAME representation on boards today is at the level of female representation in 1998," said Spencer Stuart's head of UK board practice Will Dawkins.

Many also feel that while progress is being made on the issue of women on boards, there's a long way to go. Dame Colette Bowe, who doesn't chair a FTSE board but is the chairwoman of the Banking Standards Board, told the FT: "My younger self would not have believed we would still be having this conversation."

Spencer Stuart's research also found that there are proportionally more foreign women on FTSE boards than there are foreign men. 40% of female directors are non-British nationals, compared with just 30% of men.

International representation on boards is obviously great from a diversity perspective, but Spencer Stuart warned that the trend could be indicative of a lack of female executive talent, saying that the findings could show that "boards are increasingly having to look beyond these shores to find women with the requisite experience."

In October, recruitment firm Audeliss warned that more needs to be done to encourage up-and-coming female executives in the UK. Audeliss' CEO Suki Sandhu said: "The female executive pipeline of talent is simply too slim to sustain the progress of the last five years."

One of the key issues affecting the perceived lack of female talent is the narrow way in which recruitment firms search for directors, according to Labour peer Baroness Goudie, who is a member of the 30% Club, an organisation focused on increasing the number of women in the boardroom.

In an interview with the Financial Times, she said: "They just search in this golden circle around London, they never look out to Glasgow, Manchester, Leeds."

Things are getting better, though. The final findings of the recent Davies Review, which looked into the number of women on FTSE 100 boards, shows that 26% of directors are now women. This surpassed the initial target of 25% set by Lord Davies when the review launched in 2011. At that time, only 12.5% of directors were female.