Chinese smartphone major Xiaomi is reportedly raising over $1bn from investors including the Singapore sovereign wealth fund GIC.

The fund-raising will value Xiaomi at over $45bn (£28.8bn, €36.7bn), Reuters reported.

GIC's investment in Xiaomi comes after Singapore state investor Temasek Holdings purchased a small stake in the smartphone maker in an earlier funding exercise, the report added.

Pursued by Reuters, Xiaomi and GIC refused to comment.

The fund-raising was first reported by the Wall Street Journal, which said this round was led by former Morgan Stanley analyst Richard Ji's tech fund All-Stars Investment. The exercise included Russian tech fund DST Global and Yunfeng Capital, a private-equity firm affiliated with Alibaba Group Holding's executive chairman Jack Ma.

Earlier in the month, Nomura analysts said in a note that Xiaomi and founder Lei Jun had invested in 43 firms across China's mobile internet eco-system. The targets include smart device makers, network infrastructure firms, smartphone platform developers and providers of various mobile internet services.

Nomura said Xiaomi's investment partners include Shunwei VC, Temasek and Kingsoft,

Xiaomi was the third biggest seller of smartphones in the third quarter of 2014 globally and has ousted Samsung as the biggest smartphone brand in China - one of the world's most important and fastest growing markets.

In 2013, Xiaomi Technology made a profit of 347.48m yuan (£35.7m) on 26.58bn yuan in revenue.