Prospect National Secretary Ben Marshall said: "This is great news from the UK's primary IT and telecoms company. It comes at a time when BT is investing strongly in the UK's broadband infrastructure and making advances in TV and digital media such as the creation of BT Sport.
"This represents a very significant social commitment on BT's part, as well as being a substantial investment in UK plc.
"As the union for professionals, managers and specialists, we have campaigned long and hard over the years to highlight the scale of skills shortages in key areas.
"So we are delighted that so many young people will have new opportunities to train for high-quality, skilled jobs in areas like engineering, software design, IT support, finance, logistics and digital media.
"It will provide a welcome boost for the economy, as well as for the individuals receiving these opportunities."
Prospect represents BT's 24,000 managers and professionals, and many more across the UK in the telecoms, media and IT sector.