(Adds detail on June data, background on central bank policy)
MEXICO CITY, July 9 (Reuters) - Mexico's annual inflation rate ticked up in June but remained below the central bank's ceiling, boosting bets that policymakers will leave rates at an all-time low to support tepid growth in Latin America's No. 2 economy.
Inflation in the 12 months through June was 3.75 percent, the national statistics institute said on Wednesday, below expectations of 3.78 percent in a Reuters poll and above the 3.51 percent annual rate registered in May.
The central bank unexpectedly slashed its main interest rate by 50 basis points to a record low of 3.00 percent last month, saying slack in the economy gave it room to lower borrowing costs without fanning inflation.
Policymakers have said they expect temporary factors to drive the annual rate above the central bank's 4 percent limit in the second half of the year, but that the rate should fall back toward 3 percent by early next year.
In the month of June, consumer prices rose 0.17 percent compared with expectations of 0.2 percent.
Core prices, which strip out some volatile food and energy costs, rose 0.21 percent in June versus expectations of 0.22 percent increase. (Reporting by Alexandra Alper; Editing by Nick Zieminski)