This editorial appeared in The Washington Post.

For a presidency marked by reticence to criticize Russia, Thursday offered a change of tone. The White House signed on to a multinational statement condemning Russia for poisoning people on British soil with a military-grade nerve agent. Meanwhile, the Treasury Department unveiled sanctions against five Russian organizations and 19 Russian nationals in response to Kremlin-backed meddling in the 2016 presidential election.

Both moves are welcome, but, unless they hint at much bigger things to come, and soon, they also are inadequate. These measures alone will not deter Russian President Vladimir Putin from interfering in America's 2018 elections, nor from engaging in the variety of aggressive attacks on the West that Russia continues to perpetrate.

The statement, co-signed by France, Germany and Britain, concluded that it is "highly likely that Russia was responsible" for the chilling nerve-agent attack against Sergei and Yulia Skripal in southern England, which put them in the hospital in critical condition and sickened others nearby. "There is no plausible alternative explanation," the allies insisted, noting that Russia's refusal to cooperate with British authorities underlines the Kremlin's probable guilt.

In announcing the sanctions, Treasury Secretary Steven Mnuchin cited the "ongoing nefarious attacks emanating from Russia," including election interference and cyberattacks. The Treasury Department targeted the sanctions at the Internet Research Agency, a Russian troll farm responsible for much of the Russia-backed 2016 election interference, and at Russian spy agencies, freezing their assets and blocking Americans from doing business with them. The sanctions are well-deserved.

Yet, as Sen. Mark Warner, D-Va., noted Thursday, the sanctions do not represent a dramatic change in U.S. policy. The entities and individuals sanctioned were either previously under sanction during the Obama Administration or already charged with federal crimes.

"With the midterm elections fast approaching," Warner added, "the Administration needs to step it up, now, if we have any hope of deterring Russian meddling in 2018."

The Trump administration could start by slapping more sanctions on Russian oligarchs and others in Putin's inner circle. Treasury released a list of potential targets in January. It should make better use of it. And the president should express full support for the special counsel investigation into Russian actions.

Encouragingly, Mnuchin said that he intends to impose additional sanctions "to hold Russian government officials and oligarchs accountable for their destabilizing activities by severing their access to the U.S. financial system."

Time is fast running out to deter Russian interference.