MEXICO CITY, Feb 2 (Reuters) - Mexican conglomerate Grupo Mexico on Thursday posted a 5% bump in its fourth-quarter net profit compared to a year earlier, driven by a boost in its transportation unit even as its larger mining business was hit.

Grupo Mexico, a top 10 global copper producer and a major Mexican rail operator, reported a fourth-quarter net profit landing at $1.04 billion, helped by a 60% profit boost in its transport division thanks to higher prices.

Its mining profit meanwhile dipped around 6%, it said, hurt by lower prices for copper, down 16.4% in the last three months of 2022 compared to a year earlier.

Copper production for the quarter held steady at 269,375 tonnes, added Grupo Mexico. The company, which owns Southern Copper, reiterated that output had been hampered by an "illegal blockade" at its Cuajone copper mine in Peru.

However a lift from its smaller transport division, aided by higher prices, helped revenue edge up 0.3% to $3.78 billion for the quarter.

Earnings before interest, tax, depreciation and amortization (EBITDA) landed at $2.09 billion, beating the $1.76 billion estimated by analysts polled by Refinitiv despite a 4.7% drop from the same period in 2021.

Grupo Mexico said it planned to invest around $1.83 billion in 2023, up from the $1.50 billion it spent in 2022.

The conglomerate is currently the frontrunner to buy Citigroup's the Mexican retail banking arm, known as Banamex, sources told Reuters earlier this week, saying the unit could be worth some $7 billion to $8 billion.

Grupo Mexico has secured a $5 billion debt package for the proposed acquisition, the sources said.

Citi executives said in January the divestiture was "well underway," but said an initial public offering was also a viable option. They did not give a date for the potential deal. (Reporting by Carolina Pulice, Kylie Madry, Aida Pelaez-Fernandez and Isabel Woodford; Editing by Sarah Morland and Christopher Cushing)