July 21 (Reuters) - Britain's competition regulator on Friday said auto parts provider LKQ Corp's C$2.8 billion ($2.13 billion) deal to buy Canada's Uni-Select Inc may be referred to a deeper investigation unless the companies offer acceptable undertakings to address related concerns.

The Competition and Markets Authority (CMA) has concluded that the merger between LKQ and Uni-Select could raise competition concerns in the supply of car parts and garage equipment to independent garages and workshops in 145 local areas in the UK, the regulator said in a statement.

The deal, which was announced in February, is expected to help LKQ tap into the Canadian company's strong presence in the aftermarket auto parts business.

Uni-Select and LKQ Corp did not immediately respond to a Reuters request for comment.

CMA also said that the deal could reduce competition in the supply of car parts to retail customers in 172 local areas in the country.

The companies have until July 28 to respond to the regulator, it said.

($1 = 1.3164 Canadian dollars) (Reporting by Radhika Anilkumar in Bengaluru; Editing by Nivedita Bhattacharjee)