Four of the UK's biggest insurers have started issuing January renewals on commercial business - to the relief of brokers.

Although rates have increased, particularly in property and liability lines, insurers said they had worked case-by-case rather than set blanket increases.

Royal & SunAlliance (R&SA), AXA, Zurich and Norwich Union (NU) have started sending renewals, that will continue over the coming weeks.

British Insurance Brokers' Association (Biba) chief executive Mike Williams said brokers would be relieved to see the renewal season start.

"At least there will be some clarity, after all the uncertainty, even if brokers don't like every single one of the terms put up," he said.

Over the past few months, some smaller insurers have indicated they would not issue renewals until January because they wanted first to secure agreements with their reinsurers before approaching brokers.

An R&SA spokesman said some cases which the company acquired from Independent Insurance would rise between 20% and 50%, but there were no other significant rises across the board.

"On larger risks we try to get them out in time for brokers to understand what's going on and come back with any problems," he said.

Both NU's commercial products director Jim Noakes and Axa's broker development head Colin Calder said the emphasis was "business as usual".

They said commercial property could expect larger rises than most lines.

Calder said liability could also expect significant premium increases. He said Axa's "ambition" was to raise premiums by at least 20%.

Zurich's distribution and marketing manager Dave Smith said he expected property and employers' liability lines and some motor risks to experience the most significant rises.

He said the big insurers were fortunate to have the financial stability to follow their usual renewal cycles.

"We've got a moral duty to do it," Smith said.

"We can't leave people hanging on if we're going to be a stable partner."

Allianz Cornhill has not set a date for issuing its renewals but a spokesman said it would not apply blanket rises.

"But double digit increases are possible where the premium is too low or the claims experience is poor," he said.