Technology giant Microsoft plans to create 1,000 apprentice opportunities in London over the next three years.
The announcement came at the start of a new campaign to increase the number of training places.
London Mayor Boris Johnson said the move by Microsoft was a major boost to his apprenticeship drive, which aims to deliver 20,000 new opportunities in the capital by the end of the current academic year.
Virgin Media also confirmed it will be offering nearly 90 apprenticeships this year.
Mr Johnson said: "Unemployment is a social and personal disaster which eats away at self-confidence, making people less employable.
"It is a waste of talent, a waste of hope and is hugely expensive for society. Apprenticeships can make all the difference to an eager jobseeker's prospects.”
The Mayor joined Business Secretary Vince Cable to launch National Apprenticeship Week, with the Government urging employers to help create 100,000 more apprentice places by the year 2014.
Stephen Uden, of Microsoft, said: "London is the engine room of the UK economy and, over the next three years, Microsoft intends to deliver 1,000 apprenticeships in the capital through our network of partners."
British Airways announced today that it will expand its engineering apprenticeship scheme, with the inclusion of a fourth partner in Uxbridge College.
The airline said it will be looking for 120 students, up from 90 students in 2010, recruiting them from Kingston College, Brooklands College, Farnborough College of Technology and Uxbridge College.
Government plans to triple university tuition fees to £9,000 a year from 2012 are fuelling an interest in apprenticeships, according to an ICM Omnibus poll commissioned by Pearson Training.
More than half of the 1,100 people questioned said the rising cost of higher education has made them think more positively about apprenticeships as a career choice for young people, and among 16 to 18-year-olds this figure was 55 per cent.
Nine out of 10 employers see apprentices as key to the future success of their business over the next two years, according to a new report by vocational education organisation City & Guilds.
Chief executive Chris Jones said: "Many businesses, large or small, know that apprenticeships can transform their organisation, but unless the barriers preventing more employers, particularly small and medium-sized enterprises, from hiring an apprentice are addressed, there will continue to be a gap between supply and demand.
"There will also be over 210,000 people who won't get a place at university this summer and, with our increasingly ageing population, core industry skills and quality of experience will continue to leave the UK workforce."