Nov 11 (Reuters) - Manulife Financial Corp on Wednesday said third-quarter core profit declined less than analyts had expected, helped by earnings growth in Asia and asset management, but it warned the COVID-19 pandemic posed risks.

Canada's top life insurer said the environment remains uncertain due to legal and regulatory responses to the resulting economic downturn from the pandemic.

"These disruptions, if they continue, could have a significant adverse impact on our global businesses and operations and on our financial results," Manulife said in a statement.

Manulife reported underlying profit, excluding one-time charges, of C$1.45 billion ($1.11 billion), or 73 Canadian cents a share, in the three months through September, down from C$1.53 billion, or 76 cents, a year earlier. Analysts had expected profit of 70 Canadian cents.

Higher payouts in its Canadian insurance business and lower new business volumes due to the coronavirus pandemic were offset by factors including growth in in-force business - the business it has on its books - and increased assets in its wealth and asset management unit, the company said.

Third-quarter sales fell 2% from a year earlier as the pandemic-driven declines in Hong Kong and the United States failed to offset gains in other areas.

Rival Sun Life Financial Inc last week reported better-than-expected third-quarter core earnings, benefiting from new business gains in Asia and growth in income from its asset management unit.

Manulife's net income attributed to shareholders rose to C$2.1 billion from C$723 million a year earlier as the company posted gains from investment-related experience versus losses in the prior period.

Separately, the company said it had appointed Leagh Turner, chief operating officer for Ceridian HCM Holding, to its board of directors, effective Nov. 10. ($1 = 1.3065 Canadian dollars) (Reporting by Nichola Saminather in Toronto and Niket Nishant in Bengaluru; Editing by David Gregorio)