BEIJING • Huawei Technologies has warned of its slowest revenue growth since 2013, despite making headway against Apple in global smartphones.

Revenue at China's biggest telecommunications gear maker probably rose 15 per cent to 600 billion yuan (S$123 billion) this year, rotating chief executive officer Ken Hu said in a letter to staff posted on the company's verified WeChat account.

That is down from last year when sales jumped 32 per cent. The company shipped 153 million smartphones.

Shenzhen-based Huawei has used a vast cash-generating networking business to bankroll a successful foray into smartphones, using high-end but affordable devices to push aside local rivals such as Oppo and Xiaomi.

But telecoms spending - its biggest source of revenue - is stagnant as construction of next-generation networks has not taken off.

"Our carrier business was affected by market investment trends but remains stable," Mr Hu, one of several Huawei executives who take up the CEO's post on a rotating basis, wrote in his memo.

Huawei's CEO did not discuss profitability or give division specifics in his memo, which precedes a more comprehensive results report. But the memo said it wanted to keep a closer eye on the bottom line.

The company barely grew earnings last year and has said it must reduce operational expenses.

BLOOMBERG