(QHA) -

US President Barack Obama said Thursday he was not about to impose new sanctions on Russia over the Ukraine crisis, but nevertheless signed a law giving him the authority to do so.

"The act gives the administration additional authorities that could be utilized, if circumstances warranted," the president said.

But, he added, "signing this legislation does not signal a change in the administration’s sanctions policy, which we have carefully calibrated in accordance with developments on the ground and coordinated with our allies and partners."

Obama said his administration would continue to work closely with US allies to respond to the situation and "will continue to review and calibrate our sanctions to respond to Russia's actions."

The president repeated his call for Russia "to end its occupation and attempted annexation of Crimea, cease support to separatists in eastern Ukraine."

He also noted that the United States was ready to lift sanctions if Russia de-escalates the conflict in line with a prior agreement that "respects Ukraine's sovereignty and territorial integrity."