Nasrallah delivered a televised speech to supporters in Beirut to mark the sixth anniversary of the Hezbollah war with Israel. Nasrallah said his movement was saddened by the deaths of top Syrian officials, including the defense minister, in a suicide bombing in downtown Damascus.
Hezbollah, he said, believed the only solution to the crisis in Syria was through political dialogue but expressed confidence with the Syrian military's ability to control the situation.
"We are confident that the Syrian army, which has had to cope with the intolerable, has the ability, determination and resolve to endure and foil the enemies' hopes," he was quoted Lebanese newspaper The Daily Star as saying.
At least 10,000 people have died as a result of the conflict in Syria, which began last year. Russia and China, veto-wielding members of the U.N. Security Council, voted down a resolution Thursday that would've targeted Damascus with sanctions.
British Foreign Secretary William Hague, who supports a resolution authorizing the use of force in Syria, said he was "appalled" by the action of Russia and China.
The Security Council, in a statement, also expressed "grave concern" about the security situation along the Syrian border with Lebanon. Syrian influence loomed large over political affairs in Beirut before Lebanon's Cedar Revolution in 2005.