WASHINGTON — Secretary of State Rex Tillerson said Tuesday the U.S. relationship with Russia is at an all-time low and deteriorating further, yet he cautioned against taking steps that might close off promising avenues of communication between the two former Cold War foes.

Testifying before the Senate Foreign Relations Committee, Tillerson stopped short of registering his opposition to a new package of Russia sanctions the GOP-led Senate is considering in retaliation for Moscow’s meddling in the 2016 presidential election and its aggression in other parts of the world, including Syria and Ukraine.

Tillerson told the committee that he’s still reviewing the new sanctions that Senate Republicans and Democrats agreed upon late Monday after lengthy negotiations. He said that it’s important that President Donald Trump have the flexibility “to turn the heat up” on Russia if necessary. He also said he doesn’t want promising channels of communication preemptively shut down.

Talks with Moscow on stabilizing war-ravaged Syria are progressing but it’s too early to tell if the discussions will bear fruit, Tillerson said.

Top lawmakers on two Senate committees — Banking and Foreign Relations — announced the sanctions deal amid the firestorm over Russia’s meddling in the presidential election and investigations into Moscow’s possible collusion with members of President Donald Trump’s campaign.

The plan calls for strengthening current sanctions and imposing new ones on corrupt Russian actors, those involved in human rights abuses and those supplying weapons to the government of Syrian President Bashar Assad. The package also would require a congressional review if a president attempts to ease or end current penalties.

Penalties also would be slapped on those responsible for malicious cyber activity on behalf of the Russian government.

The batch of sanctions would be added to a bill imposing penalties on Iran that the Senate is currently debating.

“The amendment to the underlying Iran sanctions bill maintains and substantially expands sanctions against the government of Russia in response to the violation of the territorial integrity of the Ukraine and Crimea, its brazen cyberattacks and interference in elections, and its continuing aggression in Syria,” said Republicans and Democrats on the committees.

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A procedural vote on the Russia sanctions is expected Wednesday, and the measure is expected to get strong bipartisan support. The legislation was worked out by Sens. Mike Crapo, R-Idaho, and Sherrod Brown, D-Ohio, of the Banking Committee, and Sens. Bob Corker, R-Tenn., and Ben Cardin, D-Md., of the Foreign Relations panel.

The legislation also allows new penalties on key elements of the Russia economy, including mining, metals, shipping and railways.

House and Senate committees are investigating Russia’s meddling and potential links to the Trump campaign, with testimony scheduled Tuesday from Attorney General Jeff Sessions. Special Counsel Robert Mueller is conducting a separate probe.

The sanctions package is rooted in legislation introduced earlier this year amid concerns on Capitol Hill that Trump may seek to lift sanctions against Russia as part of a plan to forge a partnership between the two countries in key areas, such as counterterrorism. In early January, before Trump was sworn in, a bipartisan group of senators introduced a bill designed to go beyond the punishments already levied against Russia by the Obama administration and to demonstrate to Trump that forcefully responding to Moscow’s election interference wasn’t a partisan issue.

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Then-President Barack Obama in late December ordered sanctions on Russian spy agencies, closed two Russian compounds and expelled 35 diplomats the U.S. said were really spies. Those penalties were on top of existing U.S. sanctions over Russia’s actions in Ukraine, which have damaged Russia’s economy but had only limited impact on Putin’s behavior.

A month later, senators introduced another measure that would require the president to get approval from lawmakers before easing Russia sanctions. Cardin, the top Democrat on the Foreign Relations Committee, said at the time that the measure was styled after 2015 legislation pushed by Republicans and approved overwhelmingly in the Senate that gave Congress a vote on whether Obama could lift sanctions against Iran. That measure reflected Republican complaints that Obama had overstepped the power of the presidency and needed to be checked by Congress.

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