Russian Foreign Minister Sergei Lavrov, left, and U.S. Secretary of State John F. Kerry met in Zurich on Jan. 20, 2016. (Jacquelyn Martin/Pool photo via Reuters)

Russian Foreign Minister Sergei Lavrov said Wednesday that neither Russia nor the United States supports a delay in Syrian peace talks, due to start next week, though it was not clear whether he and Secretary of State John F. Kerry had succeeded in determining which opposition groups would participate.

“We are certain that these talks must start in the next few days,” Lavrov told reporters after Kerry and he met in a hotel here in Switzerland’s largest city before they headed to the World Economic Forum in the Alpine ski resort of Davos.

Peace talks between the Syrian government and many rebel and opposition groups are to start Monday in Geneva. But the specter of a delay looms because the countries organizing the talks have not agreed on which groups constitute the legitimate Syrian opposition and which should be designated terrorist outfits. Those labeled terrorist would be banned from the talks and be exempt from a cease-fire.

Kerry has been pushing for the talks to start soon to maintain momentum. The negotiations are meant to usher in a political transition for Syria that culminates in the formation of a new government within 18 months. The United States hopes to secure a guarantee that Syrian President Bashar al-Assad will cede power, as U.S. forces look to focus on combating the Islamic State militant group, which controls vast territory in Syria and Iraq. But with Russia firmly in Assad’s corner, a guarantee of Assad’s departure appears unlikely.

State Department spokesman John Kirby said Kerry, in his meeting with Lavrov, urged Russia to use its influence with Assad to allow aid workers to deliver food and medicine to civilians trapped by the conflict. Aid workers have not been able to reach stricken areas as a humanitarian crisis spawned by the war continues to spread.

About 400,000 Syrians are trapped in besieged towns, according to estimates from the United Nations, and starvation deaths have been reported in the town of Madaya. The United Nations has accused the Assad government of blocking aid to people living in rebel-held areas. U.N. Secretary General Ban Ki-moon told reporters in Davos that the need for peace talks is urgent.

It was a dark beginning to the annual gathering of diplomats, government officials and business leaders in swanky Davos. Among those attending the World Economic Forum were diplomats from Iran and the United States, which are signatories to a recent historic nuclear deal, and Israel and Saudi Arabia, which fear that the nuclear accord empowers Iran in a way that threatens their security.

In the keynote speech at the conference, Vice President Biden said the unraveling of the middle class in the United States and other countries threatens economic growth and global security.

“When people feel that their shot at a decent life is dashed, is eliminated, the inevitable human reaction is anxiety, frustration and anger, providing fertile terrain for reactionary politicians, demagogues peddling xenophobia, anti-immigration, nationalist, isolationist views,” he said. “It begins to shred our social fabric in each of our countries. It stirs instability.”

Biden said he sees the threat materializing in third political parties emerging in Europe and in a U.S. presidential primary contest that he described as “the most unusual political campaign I have been engaged in.”

Biden and Kerry joined several other senior U.S. officials at the Davos forum this year, reflecting the intersection of foreign policy, national security and economic matters. Defense Secretary Ashton B. Carter, Commerce Secretary Penny Pritzker and U.S. Trade Representative Michael B. Froman are attending.

The alliance between Russia and the Syrian government goes back decades. Here’s a bit of historical context that explains why Russia is fighting to prop up President Bashar al-Assad, its closest ally in the Middle East. (Ishaan Tharoor and Jason Aldag/The Washington Post)

Almost certainly, the week will be far less triumphal for Kerry compared with last weekend, which was marked by the implementation of the Iran nuclear deal and the release, after 14 months of secret negotiations, of five Americans imprisoned in Iran.

Senior State Department officials said Kerry plans to give a speech on Friday focusing on the diplomatic achievements of the Obama administration, particularly in the past year. He will cite the nuclear agreement, an international climate-change pact in Paris, the restoration of diplomatic relations between Cuba and the United States and the Trans-Pacific Partnership, the officials said.

“Frankly, things are not as bad as the press would have us believing,” an aide said in highlighting the Kerry speech. “It has been a very good run over the last six months, and I think he wants to make sure that people are aware of that.”

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