As Russia launches a renewed offensive in eastern Ukraine under President Vladimir Putin, the U.K.'s defense secretary, Ben Wallace, warned that Moscow might ''dig in'' and become a ''cancerous growth'' in the country, Sky News reported Thursday.

''Well, I think it's certainly the case that Putin, having failed in nearly all his objectives, may seek to consolidate what he's got — sort of fortify and dig in, as he did in 2014,'' Wallace told Sky News, referencing Russia's annexation of Crimea.

''And just be a sort of cancerous growth within the country of Ukraine and make it very hard for people to move from them out of those fortified positions,'' he continued. ''So, I think it's really about if we want this to not happen, we have to help Ukrainians effectively get the limpet off the rock and keep the momentum pushing them back.''

Both U.S. and U.K. leaders have said they expect the conflict in Ukraine to be prolonged and are committed to supporting Ukraine for the long haul.

President Joe Biden is requesting that Congress authorize more than $30 billion in added assistance for Ukraine, administration officials said Thursday.

In the U.K., Foreign Secretary Liz Truss pressed Western nations this week to deliver heavy weapons, tanks and planes to Ukraine, warning that if Putin wins, there will be global security repercussions.

In a United Nations meeting on Wednesday, the U.S. ambassador-at-large for global criminal justice, Beth Van Schaack, asserted that there is ''credible evidence'' that Russian soldiers are executing civilians.

Russia's list of alleged war crimes in Ukraine is extensive, with the U.S. and other Western allies particularly concerned about the death toll in Mariupol, which is primarily under Russian control.

Increasingly, there is also fear that other countries may become ensnared in the conflict as it drags on.

In a statement on Wednesday, Ukrainian President Volodymyr Zelenskyy said that Russia is trying to destabilize Transnistria, a breakaway region of Moldova.

Russian troops have been stationed in Transnistria since the Soviet Union was dissolved, and The Hill reports that a Russian official recently said the Kremlin wants full control of eastern and southern Ukraine to create a path from Crimea to Transnistria.

''The goal is obvious — to destabilize the situation in the region, to threaten Moldova,'' Zelenskyy said. ''They show that if Moldova supports Ukraine, there will be certain steps.''

• US: 'Credible' Evidence Shows Russia Executed Ukrainians Trying to Surrender
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