Under the new arrangements, the mayor has more strategic powers over planning applications and will head a skills and employment board.
The LRC says that if used wisely, the powers will benefit the retail sector in the capital, bringing co-ordination and consistency to planning policies.
LRC director Nigel Smith said: 'Much-needed opportunities for retail growth and redevelopment are too often stalled by the confusing variety of policies and approaches businesses face in different parts of London. We urge the Assembly to use its new powers to ensure London attracts sustained retail investment.'
Retailers in the capital have also called for a more co-ordinated approach to waste management in London. However, Livingstone's proposals for a single London Waste Authority were not approved.