SIR Brendan Barber, the former head of the TUC, has been appointed to the board of BT's infrastructure arm Openreach.
The former trade union chief and current chairman of Acas will join telecoms veteran Edward Astle as independent members of a newly formed board that will oversee "strategy, investment and service delivery" at Openreach.
BT has faced calls from rivals to separate Openreach, and in November Ofcom ordered a legal separation of the firm.
The communications regulator stopped short of forcing a full break-up and sale of Openreach and added it remained "open" to proposals from BT for a voluntary separation of the division.
The firm said on Wednesday that the reorganisation will create "increased operational and management independence for Openreach".
But an Ofcom spokesman said: "These changes fall short of our requirements for a legally separate Openreach that delivers for all of its customers. We intend to take our plans to the European Commission later this year."
Mike McTighe, chairman of Openreach, said: "I understand that customers sometimes feel let down by Openreach because we haven't always delivered the service they expect or that we hope to provide.
"We need to do more to rebuild trust and credibility. This will be the board's focus and we are currently in consultation with BT Group about agreeing the plan to deliver better service, broader coverage and faster speeds for consumers and businesses across the country."
Meanwhile Dido Harding is to step down as chief executive of TalkTalk after seven years at the telecoms firm.
She will leave the position in May and be succeeded by the managing director of consumer, Tristia Harrison.
Ms Harding said: "After seven extraordinary and fulfilling years, during which we have transformed TalkTalk's customer experience and laid the foundations for long-term growth, I've decided it's time for me to start handing over the reins at TalkTalk and focus more on my activities in public service.
"I am very proud to be handing over to the next generation of TalkTalk leadership who, together with Charles, have played such an integral part in the success of the business to date.
"Between now and May, we will work together on a handover that maintains focus on this year's performance and enables the new team to prepare for the next financial year and beyond."
As part of a board shake-up, the group's founder Sir Charles Dunstone will step up from chairman to executive chairman.
He will relinquish his chairmanship of retailer Dixons Carphone as a result.
Charles Bligh, managing director of TalkTalk Business, will become chief operating officer.
