“They have paused with the election of a new administration in the United States, and they are looking carefully at the position of the new team,” Mr. Rood told reporters.

“My assessment is that the Russians intend to test the mettle of the new administration and the new president,” he said.

Russia’s stance on the missile shield and other issues was less flexible, Mr. Rood said, than it had been in previous talks.

Prime Minister Vladimir V. Putin of Russia said this month that the United States would quickly feel a change in attitude from Moscow if the new president altered American policies toward Russia.