Assad is under growing international pressure, including a threat of sanctions from the Arab League, over a crackdown on nationwide anti-government protests in which the United Nations says more than 4,000 people have been killed.

"We don't kill our people ... No government in the world kills its people, unless it's led by a crazy person," ABC's website quoted Assad on Wednesday as saying in a recorded interview. "Most of the people that have been killed are supporters of the government, not the vice versa."

Syrian activists say around a quarter of the more than 4,500 deaths they have recorded in nine months of protest have been among the security forces. Most foreign media have been excluded from Syria, making it hard to verify events independently.

The White House rejected Assad's remarks.

"It is just not credible," White House spokesman Jay Carney said.

"The world has witnessed what has happened in Syria. The United States and many, many other nations around the world who have come together to condemn the atrocious violence in Syria perpetrated by the Assad regime know exactly what's happening and who is responsible."

The Arab League has threatened to impose sanctions on Syria unless armed forces are verifiably withdrawn from towns and cities and a political dialogue is opened with opposition representatives.

Major Western powers as well as neighbors Turkey and Jordan are calling on Assad to step down. Turkey imposed a 30 percent duty on imports from Syria on Wednesday in retaliation for a similar tax imposed on Turkish goods.

A member of the Syrian National Council (SNC), an exile group seeking an end to Assad's rule, said the SNC would present a plan for a transition of power shortly in the next few days.

"The plan will be a sort of roadmap for a peaceful transition, with article one being that Assad has to resign and leave," said SNC member Bassma Kodmani.

"We hope that it will be supported by the Arab world and the international community," she said during a meeting with European lawmakers in Brussels.

She warned again about the threat of civil war in Syria. "The first (objective) is the protection of the civilian population, and putting an end to the killings, which might bring us into a civil war, into militarization."

FIGHTING ON HIGHWAY

Syria's official news agency SANA said the army fought back gunmen who tried to block the Aleppo highway in the tense Hama district on Wednesday and killed one "terrorist."

Experts defused seven improvised bombs in Hama district, it said. An army pilot was shot in front of his home, it said.

An activist website said an army armored personnel carrier was destroyed in clashes between troops and defectors near the radio station in the city of Saraqeb on the Hama-Aleppo highway. Heavy gunfire was reported in Hama city on Wednesday afternoon.

On the tense border with Turkey, Syrian troops opened fire in sustained bursts on Wednesday, according to residents of Turkish villages.

Peaceful protests against Assad, inspired by the Arab Spring in Tunisia and Egypt, were met with massive force as soon as they began in March.

Now Syria is creeping closer to civil war as armed opposition groups organize and move into some city districts.

Assad conceded that some members of his armed forces had gone too far, but said they had been punished.

"Every 'brute reaction' was by an individual, not an institution, that's what you have to know," he told ABC's Barbara Walters.

"There is a difference between having a policy to crack down and between having some mistakes committed by some officials," he said. "There was no command to kill or be brutal."

Asked if he regretted the violence that has beset his country, he said he had done his best to "protect the people."

Assad repeated that he was introducing reforms and elections, but said the changes could not be rushed:

"We never said we are a democratic country ... we are moving forward in reforms, especially in the last nine months ... It takes a long time, it takes a lot of maturity to be a full-fledged democracy."

Speaking of international sanctions, he said: "We've been under sanctions for the last 30, 35 years. It's not something new ...We're not isolated."

U.S. Assistant Secretary of State Jeffrey Feltman, speaking after talks in Beirut with Lebanon's Prime Minister Najib Mikati, said "Assad and his clique should stop the killing, stop the torture, stop the jailing."

"We want to use all of the tools that are available to the international community to change what is happening in Syria by peaceful means," Feltman said. That included lifting a ban on foreign media and observers imposed by "this family-owned business that is called the government of Syria."

Russia and Algeria said time should be given to the Arab League's peace plan, which calls for admission of monitors.