Tensions in Ukraine have been increasing for months after the Kremlin massed some 100,000 troops near Ukraine's border, a dramatic buildup the West says is preparation for war to prevent Ukraine from joining the NATO security alliance.
"There's no doubt we are ready to react with comprehensive, never-seen-before sanctions if Russia were to invade Ukraine again," Jeppe Kofod told reporters, declining to say what sectors would be targeted.
"Russia should know, (President Vladimir) Putin should know that the price of using provocations and military forces to change borders in Europe will be very, very high... We are ready to undertake the most severe sanctions, also more severe than in 2014," he said.
The EU, along with the United States, imposed economic sanctions on Russia in July 2014, targeting its energy, banking and defence sectors, after Russia annexed the Crimean peninsula.
US Senate Democrats have unveiled a bill to potentially punish Russian officials, military leaders and banking institutions.
But German Chancellor Olaf Scholz has urged Europe and the United States to think carefully when considering sanctions, highlighting challenges in agreeing on a joint approach.
Austrian Foreign Minister Alexander Schallenberg said that everything was on the table.
But he also pointed to Austria's dependency on Russia for 40% of its gas, adding, when asked about potential sanctions on the Nord Stream 2 pipeline, that sanctioning something that is not yet operative is not a credible threat.
"We are here to do everything we can so that war does not break out," Luxembourg Foreign Minister Jean Asselborn said.
For now, the EU does not plan to withdraw diplomats' families from Ukraine, EU foreign policy chief Josep Borrell said after Washington announced such a move.
"We are not going to do the same thing because we don't know any specific reasons. But (US) Secretary (of State Antony) Blinken will inform us," Borrell told reporters as he arrived for a meeting with his EU counterparts that Blinken is expected to join online at around 1400 GMT.
The British Embassy in Ukraine said on Monday some of its staff and dependants were being withdrawn from Kyiv.
The Kremlin has repeatedly denied planning to invade, but the Russian military already took a chunk of Ukrainian territory when it seized Crimea and backed separatist forces who took control of large parts of eastern Ukraine eight years ago.
The top US and Russian diplomats made no major breakthrough at talks on Ukraine on Friday but agreed to keep talking to try to resolve the crisis.
"Negotiations are going on", Borrell said, adding he saw no reason to leave Ukraine "unless Secretary Blinken gives us an information that justifies a move".