Frances O'Grady, general secretary of the TUC, says striking McDonald's staff are in the same situation as dock workers 130 years ago

A trade union leader is calling for a “modern-day Cardinal Manning” to support McDonald’s workers in their fight for better treatment.

In her speech at a Vatican conference today, Frances O’Grady, general secretary of the TUC, is expected to say that the demands of striking McDonalds staff – “stuck on low pay and zero-hours contracts” – were the same as those of dockers whom Cardinal Manning supported 130 years ago.

O’Grady was to make her remarks at a two-day summit of trade union leaders. The meeting, entitled From Populorum Progressio to Laudato Si’, was to be addressed by Cardinal Peter Turkson, prefect of the Dicastery for Promoting Integral Human Development.

According to an advance text, O’Grady was to say: “The Catholic Church and trade unions have a shared history in Britain. In the 19th century, Cardinal Manning supported striking dockers who demanded a pay rise, minimum hours and the right to a union voice. He called the refusal of employers to negotiate with their workers a ‘public evil’.

“This year I met the ‘McStrikers’ – young fast food workers at McDonald’s, stuck on low pay and zero-hours contracts. Their demands are the same as the dockers nearly 130 years ago. They want a fair wage, guaranteed hours and recognition of their trade union. They need a modern-day Cardinal Manning.”

Cardinal Henry Edward Manning, who served as Archbishop of Westminster for nearly 30 years from 1865 to 1892, helped resolve the London dock strike of 1889 by mediating with employers. After his death three years later hundreds of thousands of people lined the streets to pay tribute to him.

About 40 McDonald’s staff went on strike for the first time in Britain earlier this year. The workers, at two shops in Cambridge and Crayford, south-east London, are seeking a wage of at least £10 an hour.

A spokesman for McDonald’s said all its 115,000 staff were paid above the national living wage and that, by the end of the year, they would all be offered the option of guaranteed-hours contracts.

In her speech O’Grady also urged the Vatican to support trade unions and criticised the gig economy, saying workers had become “slaves” to an app.

“New global titans of technology now have wealth and power beyond our imagination. And many workers have become slaves to an app, with employers washing their hands of any notion of an employment relationship. We must offer hope that there is a better way.”

She added: “The Catholic Church and trade unions both understand that much more can be achieved together than alone. We share values of community, dignity and social solidarity, values that bind us together as workers, citizens and human beings.

“Together, we can improve working lives and put dignity for working people ahead of market forces and freedom of capital. We can build a popular alliance for economic justice, in Britain and around the world.

“So speak out and support the courageous workers who stand up against injustice. Call on your congregation to join a union. And encourage Catholic employers to do the right thing and recognise trade unions.”