Aon remains confident its merger with Willis Towers Watson will be completed soon and deliver at least the level of benefits outlined when the deal was announced a year ago.

CFO Christa Davies says the company anticipates achieving the $US800 million ($1.04 billion) in cost benefits previously flagged, even if divestments are required, and is still working towards closing the deal in the first half of the year subject to regulatory approval.

“We are continuing to work collaboratively with the appropriate regulators to gain approvals and we've offered remedies,” she told a first-quarter results briefing.

Ms Davies declined to provide details of remedies offered to competition regulators, but said any divestiture proceeds would be allocated according to the firm’s return on capital framework and highlighted the potential for share buybacks.

Aon has put forward a package of measures to address issues raised by the European Commission, which has pushed back a decision deadline to July 27. The Australian Competition and Consumer Commission is among other regulators examining the deal.

Willis Towers Watson CFO Michael Burwell told his company’s results briefing that despite the European deadline extension, the process did not necessarily have to run that long.

“It is still possible to close June 30 and be consistent with that extension,” he said.

Aon CEO Greg Case says the opportunities the companies see from the merger have evolved and strengthened in the context of the COVID-19 pandemic.

“Across every company in the world there is a bigger awareness for things like pandemic, climate, intangible assets, cyber than ever before, also up into the C-suite in ways that it hasn't permeated before,” he said. “So, for us, we see a tremendous opportunity.”

Aon first quarter revenue rose 10% to $US3.5 billion ($4.5 billion), led by gains in commercial risk solutions, while net profit rose 18% to $US913 million ($1.2 billion).

“On average globally, pricing was modestly positive, while exposures were flat, resulting in a modestly positive market impact,” the company said.