Malaysia's Perusahaan Otomobil Nasional Bhd (Proton) has reported a 48 percent year-on-year drop in third quarter earnings and warned of a tough fourth quarter, according to a Reuters report.

Reuters said that net profit fell by 48% to 196.97 million ringgit ($51.8 million) in the three months that ended December 31 from 378.25 million ringgit in the same period a year earlier.

The report added that Proton attributed the lower profit to a 20 percent drop in sales.

"The current global uncertainties will continue to impact consumer sentiment and this may affect car sales in the remaining quarter," Proton said in its financial statement.

However, The Reuters report adds that for the first three quarters combined, net profit rose 9.3 percent to 831.84 million ringgit.