The world needs to do better at stimulating economic growth, Angel Gurria, secretary general of the Organisation for Economic Co-operation and Development (OECD), told CNBC’s Street Signs Thursday.

“Our diagnosis about the world economy is that it’s better but not good enough,” Gurria said, speaking in Hamburg, Germany, ahead of a G-20 world leaders’ summit.

He emphasized the urgency needed to achieve the G-20’s economic growth target of an additional two percent globally between 2014-18, saying that progress was “lagging behind.” “We only have one more year to get there,” he warned.

Despite a “thousand different policy commitments that were made by the governments,” Gurria argued that “going collective … is the only way.”

Gurria also struck an exasperated tone over protectionist trade policies being implemented across the globe, saying that he had repeated his message “again and again and again.”

“Since 2008, there have been about 1,400 different acts that can be interpreted as protectionist on trade,” he said.