SINGAPORE (BLOOMBERG) - Reaping the rewards of going big on tech, DBS Group Holdings has pushed past Singapore Telecommunications to become South-east Asia's biggest company by market capitalisation.

Adopting a "digital to the core" strategy, Singapore's largest bank has signaled that it will focus on customers who have generated a consistently higher return on equity.

The lender had a market capitalisation of S$62.97 billion as of Thursday's close, compared with Singtel's S$60.42 billion. The telecommunications company is expected to face more competition from new Singapore mobile-phone entrant TPG Telecom Ltd.

Tech stocks from Apple to Alibaba Group Holding make up all of the world's seven biggest companies by market value amid improving investor outlook for the industry.

"Some of this optimism may be reflective of what is happening with the tech firms," said Diksha Gera, a Bloomberg Intelligence analyst in Singapore. "DBS is among the rare banks in the region who appears to be taking the challenge head-on with an extensive tech transformation."

DBS chief executive Piyush Gupta delivered his digital strategy to investors and analysts last week, seeking to lower costs and boost returns. The bank has rallied 42 per cent this year, twice the increase on the Bloomberg Asia Pacific Banks Index. Singtel added 1.4 per cent, trailing the 12 per cent gain in the Bloomberg Asia Pacific Telecommunications Index.