The Northern American ICI jumped 2.5 points to 116.4 while the European ICI rose 2.6 points to 113.6.
This was partly offset by increased pessimism among Asian investors, however, with the Asian ICI falling 7.9 points to 96.5.
The index measures investor confidence by analysing the actual buying and selling patterns of institutional investors.
A reading of 100 is neutral with investors neither increasing nor decreasing their long-term allocations to risky assets.
State Street Associates director Paul O’Connell said developed economies have entered the (northern) summer with strong momentum and that the willingness of monetary authorities to maintain liquidity has been positive for risk appetite.
“However, investor sentiment is below its February high, and remains vulnerable to signs of deflation in developed markets, and structural slowdown in emerging markets,” said Mr O’Connell
State Street Global Markets senior vice president Mike Metcalfe said the Asian ICI has now declined for a second consecutive month leaving it 18.5 points behind its March high.
“The sensitivity in the region to Chinese growth prospects and policy remains pronounced,” said Mr Metcalfe.
“The recent improvement in indices of leading indicators, together with the quasi-easing brought about by the widening of the yuan’s trading band, may provide some support to risk sentiment going forward,” he said.