LONDON — BP plc says third-quarter earnings plunged 96% as the COVID-19 pandemic reduced energy prices and demand.

The London-based oil company said today that profits, excluding one-time items and changes in the value of inventories, dropped to $86 million from $2.25 billion in the same period last year. Underlying replacement cost results rebounded from the second quarter when BP posted a loss of $6.68 billion.

BP is facing the twin challenges of reducing costs to adjust to an era of lower oil prices as the company tries to shift its focus toward renewable energy amid pressure to reduce greenhouse gas emissions that contribute to global warming. BP has pledged to eliminate or offset all of its carbon emissions by 2050.

BP says the COVID-19 pandemic continues “to create a volatile and challenging trading environment. There have been some early signs of global economic recovery. … However, the shape and pace of the recovery is uncertain, as it depends on the further spread of the pandemic.’’

Brent crude, the benchmark for international oil prices, averaged $42.94 per barrel in the third quarter, down nearly 31% from the same period last year.

Demand for aviation fuel fell about 60% from a year earlier as airlines grounded flights, BP said. Demand for retail fuels fell 7%.