SINGAPORE - Optimism among Asia's top companies has hit its highest level in two years, amid positive political changes in the region and upbeat signs from China's economy.

The Asia Business Sentiment index, compiled by Thomson Reuters and business school Insead, showed a reading of 74 in the second quarter of this year, according to a press release on Wednesday.

This marked a jump from 64 in the first quarter and was the highest level since the start of 2012.

Singapore's companies remained fairly upbeat, with an unchanged score of 67 in the second quarter. A reading above 50 indicates an overall positive outlook.

Across the region, none of the 124 companies that responded to the survey reported a negative outlook - a first in the survey's history.

The cheeriness stemmed partly from leadership changes in Thailand and India, according to the press release.