WASHINGTON - US President Barack Obama on Tuesday urged world powers to take "bold, comprehensive and coordinated" action to tackle the current global crisis.

"For the first time in a generation, the global economy is contracting and trade is shrinking," Obama wrote in an essay that the White House said was printed in 31 publications worldwide.

"Now, the leaders of the Group of 20 have a responsibility to take bold, comprehensive and coordinated action that not only jump-starts recovery but also launches a new era of economic engagement to prevent a crisis like this from ever happening again," he wrote.

The president stressed that only coordinated international action can prevent "the irresponsible risk-taking that caused this crisis," adding "that is why I am committed to seizing this opportunity to advance comprehensive reforms of our regulatory and supervisory framework."

"I also know that we need not choose between a chaotic and unforgiving capitalism and an oppressive government-run economy. That is a false choice that will not serve our people or any people," he said.

"If we continue to let financial institutions around the world act recklessly and irresponsibly, we will remain trapped in a cycle of bubble and bust," he warned.

In the essay, Obama also expressed his opposition to rising protectionism. "We should embrace a collective commitment to encourage open trade and investment, while resisting the protectionism that would deepen this crisis," he wrote.a