A shadow minister sacked after appearing on a picket line joined BT workers striking in central London on Friday as the row over over Labour’s support for unions deepened.
Sam Tarry told a rally of communications staff that they needed “a Labour leadership that is prepared to stand up and does not look the other way when BT workers are going to foodbanks”.
The Ilford South MP was fired from his role as a shadow transport minister earlier this week following media appearances at an RMT picket line during the rail strikes.
Sir Keir Starmer had banned his MPs from appearing at striker protests, but several defied his orders.
The Labour leader said Mr Tarry lost his job for making up party policy “on the hoof” during unauthorised TV appearences.
Addressing the Communication Workers Union (CWU) protest outside BT Tower, Mr Tarry said: “It is not good enough for the Labour Party to say that we probably won’t be able to give you a pay rise in line with inflation.
“That means the Labour Party is committed to cut people’s wages in real terms and that is totally unacceptable.
“If I’m sacked for having said that on TV and not supposed to have been on that picket line then people need to have a really hard think about what the Labour Party is for.
“Because for me the clue is in the name: Labour. On the side of working people.”
Thousands of BT workers walked out this morning in the first of two days of strikes.
Engineers and call centre staff voted for industrial action after BT offered them a £1,500 below inflation wage rise.
It is the first large national telecoms strike since 1987.
It follows large scale industrial action by rail unions, who walked out in June and earlier this month with further strikes planned this weekend and in August.
Doctors, nurses and teachers are also among the professions who have raised the prospect of industrial action over pay deals, as the threat of a national strike looms.
CWU General Secretary Dave Ward said unions were "talking about forms of collective action further on in the summer that all workers can participate in".
He added that BT had imposed a "pay deal on the workforce this year that is simply insufficient in the situation with the cost of living crisis". It follows the company recording more than £1billion in profits last year.
Mr Ward told Sky News: "This level of inequality and the way that workers are being treated verses the companies themselves, this can’t continue.
“People are not going to put up with it.”
BT said it engaged in "exhaustive discussions" with the union before deciding on a £1,500 rise which it claimed was its "highest pay award in more than 20 years" for workers.
"We have confirmed to the CWU that we won’t be reopening the 2022 pay review, having already made the best award we could," a statement said.