Aon says it is considering making an offer for rival Willis Towers Watson, in what could be the biggest merger in the global broking sector.

“The company confirms that it is in the early stages of considering an all-share business combination with Willis Towers Watson,” Aon said in a statement this morning.

“The company emphasises that, at this point, its evaluation of a potential transaction is at a preliminary stage and there can be no certainty that any transaction will take place nor as to the form or terms on which any transaction might be pursued.”

Aon, which has more than 50,000 employees in 120 countries, says a further announcement will be made in due course, as appropriate.

Willis Towers Watson was created from a merger in 2016 of global broker Willis Group and professional services consultant Towers Watson.  The combined firm, which has roots dating back to 1828, has some 45,000 employees in more than 140 countries and markets, the company says on its website.

Aon’s announcement follows Marsh & McLennan’s decision last year to launch a takeover for JLT in a $US5.6 billion ($7.9 billion) deal.

That transaction is expected to close in the northern spring, subject to regulatory approvals.

More details in our regular bulletin on Monday.