Secretary of State Rex Tillerson warned lawmakers on Wednesday not to pass sanctions legislation that could preclude "constructive dialogue" with Russia.

Senate lawmakers agreed to a package of sanctions punishing Russia for interfering with the 2016 presidential election, destabilizing Ukraine, and supporting Syrian President Bashar Assad in an ongoing civil war. That legislation is expected to pass as part of a suite of sanctions targeting Iran, which is Russia's partner in Syria. Tillerson didn't make his opposition explicit, but he offered a cautionary "point of view" about the bill.

"I would urge Congress to ensure any legislation allows the president to have the flexibility to adjust sanctions to meet the needs of what is always an evolving diplomatic situation," Tillerson told the House Foreign Affairs Committee at the opening of a hearing on the State Department's budget request. "Essentially, we would ask for the flexibility to turn the heat up when we need to, but also to ensure that we have the ability to maintain a constructive dialogue."

The legislation is designed to give President Trump minimal flexibility in deciding if the sanctions must be imposed, according to a Senate Democratic aide familiar with the bill's development. It gives him the option of issuing a waiver to the Russians if they change the offending policies that provoked the sanctions, but the waiver rules "really make it hard for the president not to impose sanctions," the aide told the Washington Examiner.

Tillerson emphasized the need for "flexibility" to negotiate with the Russians on a variety of thorny issues. "I certainly agree with the sentiment that has been conveyed by several members from both parties that Russia must be held accountable for its meddling in U.S. elections," he said.