BEIJING, July 23  -- China has lived through its worst economic slowdown in the first half thanks to its resolution for deepen reform, a prominent economist said on Wednesday.

"I am hopeful that the worst of the slowdown has now passed," said Stephen Roach, former chief economist of Morgan Stanley, noting encouraging breakthroughs have been made in pushing ahead reform.

He said that during his new book launch for Unbalanced: The Codependency of America and China in Beijing.

China's year-on-year economic growth rebounded to 7.5 percent in April-June period after the weakest quarterly reading in the first quarter since the third quarter of 2012. An array of other economic indicators from exports to investment also saw gradual recovery, indicating the world's second largest economy is gaining strength.

Predictions from economic research institutes have turned optimistic that China's economy will continue to stabilize in the second half and 7.5 percent growth will be realized.

Despite downward pressures, China's determination to reform remains unshakable this year with high hopes of new opportunities to boost thw economy by overall restructuring.

"If the economy in fact stabilizes at 7-percent range, there is no reason to back off reform agenda. That's again very good news for medium to longer-term stability of the Chinese economy," Roach said.

He noted the significance for the Chinese central government to keep the courage to push forward reform and fend off pressures from power blocs to resist the changes.

He eyed China as an emerging economic leader in Asia playing an important role in driving the global economy.