ICG invests in private equity, credit and real assets and has seen demand surge in recent years as institutional investors looked to increase allocation to such 'alternative' assets offering higher returns than traditional stock and bond markets.

Total assets in the year to end-March were 37.1 billion euros (32.6 billion pounds), boosted by 10 billion euros in inflows from third-party clients.

ICG's Fund Management Company, which includes external capital and is the main driver of revenue, saw assets rise 41% to 29.6 billion euros, helping underpin a 65% increase in adjusted group pretax profit to 278.3 million pounds.

ICG said it planned a final ordinary dividend of 35 pence a share, up 67% on the prior year and that the outlook remained strong, with good visibility on its fundraising pipeline.

"This has been an excellent year for ICG," Chief Executive Benoit Durteste said, with "strong demand across a broad range of our investment strategies".

At 0702 GMT, shares in ICG were up 8.4% to 1,298 pence a share, the biggest gainer on the FTSE mid-cap index.

Julian Roberts, analyst at Jefferies, said the results had exceeded expectations and reinforced his positive view of the company, flagging a 'buy' rating and 1,509 pence target price.

"The fundraising and deployment outlook remain positive, the dividend is clearly on a strong footing, even after a 50% increase and we continue to see ICP [ICG] as the pick of the asset managers," he wrote in a note to clients.

(Reporting by Simon Jessop, editing by Louise Heavens)

By Simon Jessop