To address the first point, the
UK expressed deep regret for its role in the slave trade some years ago.
http://news.bbc.co.uk/1/hi/6185176.stm
(As a Brit, I want also to mention that the
UK played a major role in ending the western slave trade in the 19th century.)
I am not sure what such apologies are worth, however if they offer consolation to the descendants of slaves, that is something.
Turning to the second point, such forms of bondage are sadly widespread in many countries, not just India. The rest of the world should keep up pressure to end such abuses.