UNITED KINGDOM – Aon Plc has it would buy Willis Towers Watson Plc for nearly US$30 billion, in an all-stock deal.

Reuters reported that the deal will make Aon the world’s biggest insurance broker and give it more pricing power, but also attract regulatory scrutiny.

The acquisition, the largest ever in insurance sector, unifies the second and third largest brokers globally into a company worth almost US$80 billion, overtaking market leader Marsh & McLennan Companies Inc.

The deal comes at a time when insurers are facing rising claims and new threats from the global outbreak of coronavirus and climate change.

Last year, Aon had scrapped plans to pursue a merger with Willis, a day after media reports forced it to reveal it was in the early stages of considering an all-stock offer for the Irish-domiciled company, according to Reuters.

The merger agreement came right after a 12-month restriction under Irish rules for revisiting the deal expired.

The timing also coincides with a violent market correction, as Wall Street’s main stock indexes plummeted and the Dow Jones Industrials crashed 2,000 points on Monday, driven by 20% slump in oil prices and the rapid spread of coronavirus.

When asked about the timing of the deal, Aon Chief Executive Officer Greg Case said: “This is the time we move,” noting that he spoke to 250 senior colleagues who were “energized” by the deal.

As a result of the deal, Aon shareholders will own about 63% and Willis investors about 37% of the combined company.

Aon reports that the company will keep headquarters in London and be led by Aon CEO Case and Aon CFO Christa Davies while Willis’ CEO John Haley will become executive chairman.

Aon and Willis put together insurance contracts for clients that involve a number of insurance providers, for anything from airlines to large sporting events.

The brokers also play a key deal-making role in the 330-year-old Lloyd’s of London commercial insurance market, which carries out much of its business face-to-face and insures specialist risks like oil rigs and soccer stars’ legs.

Aon and Willis also provide investment and employee benefits advice, and broker deals for reinsurers, who share part of insurers’ exposure to potential large losses like hurricanes, in return for part of the premium.

The combined entity will work across risk, retirement and health businesses. The deal will also allow the “new” Aon to offer clients services in areas like cyber, intellectual property and climate risk, executives said.