Reports suggest that as well as Los Angeles and Phoenix, the supermarket group is looking for sites in Las Vegas.
It has also registered its two US subsidiaries in Nevada, California and Arizona.
Tesco announced in February this year that it planned to enter the US market in 2007, with a c-store format on the west coast.
Since then its plans have been kept under wraps. However,
this week The Grocer revealed that it is currently advertising for a range of roles on a careers web site, including non food buyer and operations development manager.
Last month, Tesco US chief executive Tim Mason told The Grocer that it had built up a team of 60 people in the US and would create a head office in El Segundo, California.