The first quarter was the most favorable pricing environment in the U.S. and London wholesale markets in a number of years, according to Chubb Ltd.'s top executive.

The market continued to improve from the first of the year through April, a period that saw premium price changes matching loss costs trends in North America, Chairman and CEO Evan Greenberg said during a conference call to discuss earnings. Rates improved for many property and casualty lines, including general casualty for primary and excess lines and in D&O and professional lines, he said.

Net premiums for P&C were up more than 5%, and retention remained strong across all of North American P&C lines, Greenberg said. Chubb saw a 4% improvement in major accounts and specialty lines excluding agriculture. Renewal increases for major accounts was nearly 5%, with similar percentage climbs for risk management, excess casualty and also for property, which was up 9% on the quarter, the CEO said.

Premiums for middle market and small commercial business in North America posted a 6.5% increase, marking the best growth quarter since Chubb's merger with ACE Ltd., Greenberg said. Internationally, business is growing along with the improved pricing environment, which included a 2% expansion in overall retail rates and an 8% increase in rates for the London wholesale open-market business.

The rate of pricing increase accelerated in short and long-tailed lines in the U.S. and London, the CEO said.

The market has been rational for the first time in years, according to Greenberg, and is producing growth momentum. "I like the tone of the market; I like what I see and what I feel," he said.

The pricing environment improved especially well in large accounts and E&S, Greenberg said. Middle market lines also grew, but not at the same rate as larger accounts, the CEO added.