Aon has today scrapped plans to pursue a merger with rival insurance brokerage Willis Towers Watson.
This comes a day after it revealed it was in early stages of considering an all-stock offer for the Irish-domiciled company.
Aon's shares rose 4.3% today, recouping some of the losses incurred yesterday after news of the potential merger surfaced.
The company did not give any reason for abandoning the deal.
An Aon-Willis merger would have been the largest deal in the US insurance industry that is consolidating in the face of uncertainty arising from Brexit and trade tensions between the US and China.
Shares of Willis Towers hit an all-time high of 8.6 % yesterday after a Bloomberg report said the companies were in preliminary talks. Aon's shares fell nearly 8%.
Following the report, Aon was forced to confirm that it was in early stage talks with Willis Towers due to Irish regulatory requirements, the company said.
"As a result of media speculation, those regulations required Aon to make the disclosure at a very early stage in the consideration of a potential all-share business combination," the insurer said in a statement.