LAUSANNE, Switzerland, March 29 -- Chinese Foreign Minister Wang Yi arrived in Switzerland's lakeside city of Lausanne on Sunday to join the ongoing Iran nuclear talks in an effort to push forward the expected framework agreement.

Wang is expected to hold bilateral talks with his Iranian counterpart Mohammad Javad Zarif, U.S. Secretary of State John Kerry, High Representative of the European Union for Foreign Affairs and Security Policy Federica Mogherini and Russian Foreign Minister Sergei Lavrov respectively later on the day, sources close to the Chinese team told Xinhua.

Mogherini, French Foreign Minister Laurent Fabius and German Foreign Minister Frank-Walter Steinmeier had arrived in Lausanne on Saturday while British Foreign Secretary Philip Hammond and Lavrov are planned to arrive on Sunday.

With all the top diplomats of the P5+1 (namely the United States, Britain, China, France, Russia and Germany) gathering in Lansanne, there are increasing signs that a framework agreement might be reached before the March 31 deadline.

The six major world powers have been negotiating with Iran very frequently since the beginning of 2015 in an effort to put Iran's nuclear program under international control.

On November 24 of 2013, the P5+1 and Iran reached a first-step agreement on Iran's nuclear program, the Geneva 2013 Joint Plan of Action, which demanded Iran to suspend some sensitive nuclear activities in exchange for limited sanction relief to buy time for the diplomatic effort to resolve the issue.

Since then, the P5+1 and Iran have twice missed self-imposed deadlines for a final and comprehensive accord, in June and November respectively. The negotiators then set March 31 of 2015 as a new deadline for a political framework agreement and June 30 for the final deal.