By Anton Bridge

TOKYO Rakuten Group shares surged on Monday morning after the e-commerce giant reported narrowing losses at its cash bleeding mobile unit last week alongside assurances that it can cover its debt burden for the next financial year.

Shares jumped as much as 5.2% when markets opened, hitting 596.9 yen before shedding some gains. Japanese markets were closed on Friday for a holiday.

The April-June period was Rakuten's 12th straight quarter of losses as its mobile offering has failed to bring in the customers to cover the immense costs of building out the network.

But cost-cutting efforts appear to be bearing fruit.

A Jefferies research note published after last Thursday's earnings release credited Rakuten's roaming agreement with KDDI, one of Japan's three incumbent networks, as enabling cost improvements at the newcomer.

Rakuten has taken to publicly listing its more successful units to generate cash, listing its internet banking business - Rakuten Bank - in April and applying to list its securities business in July.

Last week, Rakuten also announced plans to consolidate its payments and points businesses and fold them into Rakuten Card, its credit card and loans unit. It left open the possibility of listing the business in the future.

Rakuten also committed to taking on no additional gross debt, instead using equity-related financing to reduce its debt burden.

The group has a total of 1.9 trillion yen ($13.11 billion) in debt, with 406 billion yen due in 2024 and a further 430 billion yen in 2025, according to Refinitiv data.

($1 = 144.9500 yen)

(Reporting by Anton Bridge; Editing by Jacqueline Wong)