WASHINGTON — The State Department accused the Syrian government on Wednesday of retaliating against the Syrian opposition’s representatives to the Geneva peace talks by arresting their family members.

There have been two rounds of unproductive talks in Geneva between the Syrian opposition and a delegation from the Syrian government, which is led by President Bashar al-Assad.

Secretary of State John Kerry has blamed the Assad government for the deadlock in the talks and said that it had undermined them by putting opposition delegates on a terrorist list and seizing their assets. On Wednesday, the State Department asserted that the Syrian government had also been detaining some of the delegates’ relatives.

“The United States is outraged by reports that the Assad regime has arrested family members of the Syrian Opposition Coalition delegation to the Geneva II peace talks, designated delegates as terrorists and seized delegates’ assets,” Jen Psaki, the State Department spokeswoman, said in a statement.