WPP takes its stake in Chime Communications to one fifth of the company. It has backed Chime since 1997.

Media company WPP on Friday increased its stake in public relations company Chime Communications, which runs businesses including Bell Pottinger, to above 20%.

Chime said WPP now held 16.4 million ordinary shares in Chime.

WPP first invested in Chime, which is chaired by Lord Bell, in 1997, according to WPP’s website.