DAMASCUS/UNITED NATIONS: International efforts to destroy Syria’s chemical weapons stockpiles will shift into high gear Tuesday, as Damascus is refusing to talk with the main Western-backed opposition group in a blow to U.S.-Russian efforts to hold a peace conference by November.

Twenty inspectors from the Netherlands-based Organization for the Prohibition of Chemical Weapons landed in Beirut Monday and will travel to Damascus to begin their ambitious task, a complex and potentially explosive mission fraught with security challenges.

Inspectors at The Hague said the their first priority was to help the country scrap its ability to manufacture chemical weapons by a Nov. 1 deadline, using every means possible.

That may include smashing mixing equipment with sledgehammers, blowing up delivery missiles, driving tanks over empty shells or filling them with concrete, and running machines without lubricant so they seize up and become inoperable.

Some of the inspectors will double-check Syria’s initial disclosure of what weapons and chemical precursors it has and their locations, while others begin planning the logistics for visits to every location where chemicals or weapons are stored.

Within a week a second group of inspectors will arrive and form teams that will fan out to individual sites.

The inspectors have about nine months to find and dismantle an estimated 1,000-ton chemical arsenal that took years to build – the shortest deadline they have ever faced in any nation, and their first mission undertaken in a country at war.

Another U.N. team of inspectors charged with investigating alleged chemical attack sites Monday concluded its almost weeklong mission, which involved investigating a total of seven locations.

The team initially visited Syria last month to investigate three alleged chemical attacks earlier this year. Days into the visit, the rebel-held Damascus suburb of Ghouta was hit by a chemical weapons attack, and the inspectors turned their attention to that case. The inquiry determined that the nerve agent sarin was used in the Aug. 21 attack, but it did not assess who was behind it.

The team will now draft its final report on its findings about the chemical weapons attacks in Syria, expected to be ready by the end of October, according to U.N. spokesman Martin Nesirky in New York.

Meanwhile, Syrian Foreign Minister Walid al-Moallem put a damper on efforts to move ahead with a planned peace conference, saying senior Damascus government officials would not sit down to talk with the Syrian National Coalition because it had supported a planned U.S. strike.

Moallem told Al-Mayadeen TV late Sunday that the group “is not popular in Syria and lost a lot among Syrians when it called on the U.S. to attack Syria militarily.”

He also lashed out at the rebels when he addressed world leaders Monday at the United Nations General Assembly, repeating claims that his government was fighting a war mostly against Al-Qaeda-linked militants.

Moallem invoked the Sept. 11, 2001, attacks on the United States, remarks that Washington dismissed as offensive and disingenuous.

Addressing the U.N. General Assembly, Moallem also said “There is no civil war in Syria, but it is a war against terror ... The people of New York have witnessed the devastations of terrorism, and were burned with the fire of extremism and bloodshed, the same way we are suffering now in Syria.”

The U.S. mission to the U.N. said Moallem’s comment was “as disingenuous as it is offensive,” adding that his statements “have no credibility.”

“The fact that the Syrian regime has shelled schools and hospitals and used chemical weapons on its own people demonstrates that it has adopted the very terrorist tactics that it today decried,” said Erin Pelton, spokeswoman for the U.S. mission.

Moallem repeated the government’s position that it is the rebels who have been using poison gas.

For his part, French Foreign Minister Laurent Fabius said Britain, France and China would be involved in the Geneva peace conference, rebuffing a claim by Assad that the Europeans had no role to play.

Fabius told France Inter radio that Geneva II should aim to agree on a “transition government for a united Syria that respects minorities.”

“In Geneva II, we want to find an accord between the representatives of the regime and the moderate opposisition, so that it is not the terrorists, the extremists, Al-Qaeda who reap the benefits,” he added.

Separately, Turkey’s Parliament Thursday will discuss a government motion authorizing military strikes against Syria, the deputy prime minister said. 

Bulent Arinc declined to comment on its scope while speaking after a weekly Cabinet meeting. Turkey authorized military action against Syria shortly after a mortar bomb attack fired from the neighboring territory killed five of its civilians in October 2012. 

Also, a mortar bomb hit the Chinese Embassy in Damascus Monday, damaging the building and wounding one person, Chinese state media reported. 

China’s state news agency Xinhua said opposition forces had launched the shell, which fell into the embassy and damaged doors and windows, inuring a Syrian employee.

Foreign Ministry spokesman Hong Lei said in a statement that China was “shocked by the incident and strongly condemns it.”