Three weeks ago in Vienna, Mr. Kerry appeared before reporters to declare
that if Mr. Assad continued to obstruct humanitarian convoys, the West would help the United Nations
relief agency conduct airdrops of supplies to starving towns, beginning June 1. The deadline passed with little comment by Mr. Kerry or the State Department. It remains unclear when those airdrops will commence, if at all.
At the same Vienna conference, Mr. Kerry rejected the notion that President Obama and other allies would not use force to stop the Syrian government’s indiscriminate bombings or enforce humanitarian access.
“If President Assad has come to a conclusion there’s no Plan B,” he said, “then he’s come to a conclusion that is totally without any foundation whatsoever and even dangerous.”
Mr. Kerry, administration officials said, submitted to the White House months ago a “Plan B” that called for escalated military action if Mr. Assad continued his defiance. Mr. Obama has not acted on it, telling aides he was not convinced the plan could make a significant difference, especially since Syria’s Arab neighbors and European powers have not offered more than token support.
Mr. Obama is wary of drawing the United States deeper into a conflict in which he initially saw no vital American interest. Mr. Kerry and other officials, in private, have argued that the size of the humanitarian disaster in Syria
and the flow of refugees into Europe have created such an interest. But with only seven months left in office, Mr. Obama seems unlikely to change his mind.
Mr. Assad spoke as the Syrian authorities imposed new obstacles on international efforts to transport emergency aid to civilians trapped in rebel-held areas. United Nations officials in Geneva said government approval was withheld for a delayed food convoy to Daraya, a suburb of Damascus that received medical aid last week for the first time in four years.
Mr. Assad was clear on Tuesday that he had no intention of compromising with his adversaries, and seemed to reject the next deadline: an Aug. 1 target for developing a “transition plan” that Mr. Obama and Mr. Kerry have said must ultimately result in someone else running what is left of Syria.
In his speech, Mr. Assad said the peace talks that broke down were a “booby-trapped” effort by opponents who have been seeking to depose him since the war started in 2011, during the Arab Spring.
“When they failed to achieve what they wanted, their response was an open declaration of supporting terrorism,” Mr. Assad said in the speech made in Parliament, as reported by the state news agency
and broadcast on national television.
Mr. Assad’s adversaries reacted with a mix of fury and frustration. “We’re seeing behavior that is the most extreme, the full military solution,” said Bassma Kodmani, a member of the [Saudi-led] High Negotiations Committee, an opposition group that had been negotiating with the Syrian government through United Nations mediation.
“Seventeen countries have agreed on something, does this have no value at all?” Ms. Kodmani said.
Mr. Assad seems unlikely to be able to make good on his boast to retake his country. His strength is largely limited to areas where there is a strong presence of his minority Alawite sect.
But bolstered by Russia’s intervention nine months ago to help prop him up, Mr. Assad is stronger than he has been in years, many experts say, and he has rejected the idea that any new government would have to exclude him.
He has the strong support of Iran, his longtime provider of security, though Russian officials seem less concerned about whether Mr. Assad himself remains in power.
by President Vladimir V. Putin of Russia in March that he was pulling back from Syria appeared to be largely a charade.
Russian airstrikes helped the Syrian Army retake the ancient city ofPalmyra
from the Islamic State that same month. The Russians have also been helping Assad loyalists elsewhere, including against insurgents in and around the city of Aleppo and other parts of northern Syria. Some of these groups are supported by the United States.
“Just like we liberated Palmyra and many other areas before it,” Mr. Assad said in the speech, “we are going to liberate each and every inch of Syria from their hands because we have no other choice but to win.”
Behind the scenes, Mr. Kerry has been talking frequently to Russia’s foreign minister, Sergey V. Lavrov, to seek assurances that Russia was aiming first at Islamic State forces, and not bombing other insurgent groups. State Department officials offered no details of those discussions, repeating a standard line that they are asking Russia “to use its influence” to allow humanitarian intervention. There appears to be no plan to turn the calls for airdrops — which Mr. Lavrov echoed — into a reality.
At the same time, evidence suggests that many of the groups the United States is backing are under periodic attack from Russia and ground forces supported by Iran.
“It’s pretty clear Assad’s defiance and rigidity at the negotiating table continues to increase after the Russian intervention,” said Andrew J. Tabler, a Syria expert at the Washington Institute for Near East Policy. “This doesn’t bode well for the political negotiations in Geneva to find a political settlement.”