New York leaders Davis Polk & Wardwell and Simpson Thacher & Bartlett have secured the lead roles on the $16.5bn (£9.7bn) creation of St Paul Travelers in the latest evidence of the rebirth of big ticket US M&A.

The deal sees insurance and asset management group The St Paul combine with rival Travelers Property Casualty to create a company with $107bn (£62.9bn) in assets.