China on Sunday opened the G20 summit, bringing the leaders of the world's largest economies together to discuss boosting global growth.

Opening the two-day summit in Hangzhou, Chinese President Xi Jinping said the world economy is improving, but added that countries face challenges in finance, trade and investment.

"I hope that in Hangzhou we can address both the symptoms and root causes of global economic problems ... The G20 should change its approach and put equal importance on short-term and long-term policies," Xi said.

"We should make the G20 an action team instead of a talk shop," Xi added at the opening, in response to criticism that the annual summit fails to yield concrete action.

The G20 also provides world leaders a chance to discuss other pressing issues, including the Brexit, South China Sea dispute, refugees and Syria.

However, not everyone was pleased with the summit's opening. Non-government organizations decried the lack of access they had at the event. DW journalists have also been prevented from reporting on the summit.

Bilateral talks are a regular feature on the sidelines of the summit and several such meetings were held even before the summit officially opened.

US President Barack Obama and Xi met Saturday and agreed to enter the Paris climate agreement.

German Chancellor Angela Merkel spoke with Turkish President Recep Tayyip Erdogan about the July 15 failed coup attempt and the refugee crisis. Obama also met with Erdogan to discuss the coup attempt, Syria and the fight against the "Islamic State."

BRICS, a group of five major emerging economies including Brazil, Russia, India, China and South Africa, held an informal meeting to discuss economic cooperation.

(DW)