Beijing will work with all parties in the Syria conflict to push for the "difficult but correct" step toward a political solution to the crisis, China's top diplomat said on Wednesday.

The international community is looking forward to an early start to the third round of talks between the Syrian government and the opposition that is coming at a critical stage in the crisis, Foreign Minister Wang Yi said in Beijing during a meeting with Ahmad Jarba, president of the National Coalition for Syrian Revolutionary and Opposition Forces.

Jarba is leading a delegation of Syrian opposition leaders on a four-day visit that ends on Friday.

Wang said the continuous turbulence has caused thousands of Syrians suffering, while urging all parties in the conflicts to cease fire and advance a tolerant political transition.

"The negotiations between the two sides were tough. However, despite enormous difficulties, one thing I am sure is that both sides have shown interest in continuing the negotiations," Wang said.

The coalition, founded in Doha, Qatar, in November 2012, is considered the war-torn country's most influential opposition force. On his first official visit to China, Jarba met Vice-Foreign Minister Zhang Ming.

Jarba said the coalition, which is committed to safeguarding the rights of the Syrian people, supports a political solution as the best way to end the crisis.

"In its fourth year, the political and humanitarian crises in Syria have reached an unbearable point," Jarba said. "If the Syrian government shows sincerity, we are willing to participate in future negotiations.

"As a permanent member of the United Nations Security Council, China has maintained positive relations with various parties. We hope China will play a more important role in facilitating a balanced proposal."

Chinese analysts said the coalition is hoping the visit will draw greater understanding and support from China.

Gao Zugui, director of the Institute of World Politics of the China Institute of Contemporary International Relations, said the opposition is placing a greater focus on negotiations and trying to appeal to the major powers following a series of setbacks on the ground in Syria.

"Among the permanent members of the UN Security Council, Western countries stand with the Syrian opposition while Russia supports the current regime," Gao said. "Under these circumstances, the coalition hopes this visit will be a chance to present their case to China and influence Beijing's stance."

Gao said China's voice is growing stronger and more positive on the Syrian issue.

Yin Gang, an expert on Middle Eastern studies with the Chinese Academy of Social Sciences, said China can play the role of coordinator and promoter of dialogue.

"The coalition will respect China's position and partly adopt our suggestions," Yin said. "The key stakeholders are the Syrian government, the opposition and outside factors such as the Gulf Cooperation Council, League of Arab States, Europe and the US."

The UN-backed Geneva II Conference on Syria that reconvened in Switzerland in January didn't achieve any resolution to the crisis, with the coalition, which negotiated on behalf of the opposition, calling for the ouster of President Bashar al-Assad as one of its key demands.

On Tuesday, Syrian troops and pro-government militiamen fought their way into rebel-held neighborhoods of the central city of Homs after besieging them for nearly two years. Syrian television reported that the government forces "have achieved key successes in the Old City of Homs", AFP reported.

A UN operation in February evacuated some 1,400 people trapped inside Homs, but around 1,300 people, mostly fighters, remained behind with dwindling food and medical supplies.

The crisis erupted in 2011 with anti-government protests. It rapidly evolved into armed conflict joined by radical jihadist movements. The UN estimates that around 100,000 people have been killed during the conflict.

He Liu and AFP contributed to this story.