US President Donald Trump, facing a tough presidential election battle this November, has promised to use his own funds to fill campaign coffers if necessary, The Guardian reports.

"If I have to, I will," Trump told reporters today. "Whatever it takes, we have to win."

Meanwhile, campaign financing figures released by the Biden camp show that the Democratic contender has broken the monthly fundraising record by a huge margin, raising $364.5 million in August. The Republican party has yet to release its corresponding figures.