President Joe Biden said Friday he is “convinced” that Vladimir Putin has decided to invade Ukraine within the week, an event that would trigger Western sanctions set to turn Russia into what a US official called a “pariah.”

“As of this moment I’m convinced he’s made the decision,” Biden said in televised remarks at the White House.

Biden said the attack could come in the next “week” or “days” and that targets would include the capital Kyiv, “a city of 2.8 million innocent people.”

The US leader insisted it was “not too late to de-escalate and return to the negotiating table,” but warned that if an attack comes, the Russian president will have “slammed the door shut on diplomacy.”

The Kremlin insists it has no plans to attack its neighbor, which has angered Russia by seeking long-term integration with NATO and the European Union.

However, the United States says that with an estimated 149,000 Russian troops on Ukraine’s borders — as many as 190,000, when including the Russian-backed separatist forces in the east — it’s only a matter of when.

Adding to jitters, Russia’s defense ministry announced that Putin would personally oversee previously scheduled drills involving nuclear-capable missiles on Saturday.

And on the ground in Ukraine’s disputed east, sporadic clashes fed a growing sense of dread.

An AFP reporter near the front between Ukrainian government forces and the pro-Russian territory in the Lugansk region heard explosions and saw damaged civilian buildings on Kyiv’s side of the line.

There were growing fears that only a spark — which Washington warns could be a deliberate “false flag” incident created by the Russians — might now be needed to set off the largest military confrontation in Europe since World War II.

A US defense official said that more than 40 percent of the troops surrounding Ukraine were now “uncoiled” in a position to go on the offensive.

– ‘Pariah’ –

Biden spoke on Friday with fellow NATO allies in a conference call to cement plans for Western economic sanctions against Russia should its troops attack Ukraine.

“We continue to remain in lockstep,” Biden said afterward.

According to a senior official, the sanctions package will be devastating.

“If Russia invades Ukraine, it would become a pariah to the international community,” the deputy US national security advisor for international economics Daleep Singh told reporters. “It will become isolated from global financial markets and be deprived of the most sophisticated technological inputs.”

Singh predicted “intense capital outflows, mounting pressure on its currency, surging inflation, higher borrowing costs, economic contraction, and the erosion of its productive capacity.”

– ‘False flags?’ –

In the eastern separatist areas of Donetsk and Lugansk, Moscow-backed leaders sought to flip the narrative of Russia being the aggressor.

Accusing Kyiv of planning its own offensive to retake the eastern territories, they said the government’s forces were carrying out sabotage missions. Civilians were ordered to evacuate.

But US Secretary of State Antony Blinken accused the Kremlin of mounting a propaganda campaign to create an excuse for war.

Blinken told the Munich conference what has happened “in the last 24 to 48 hours is part of a scenario that is already in place of creating false provocations, of then having to respond to those provocations and then ultimately committing new aggression against Ukraine.”

Ukraine’s foreign minister said “Russian disinformation” about a supposed Ukrainian attack was being spread to fuel the war fever.

Biden praised Ukraine’s military for showing “restraint” and “great judgement,” saying the allegation that they were the ones preparing aggression “defies basic logic.”

– Putin sees ‘deterioration’ –

Both sides in the east of Ukraine claimed the other was stepping up the violence amid low-level exchanges of fire.

Videos circulating on Russian-language social media showed sirens sounding in Donetsk as Moscow-backed separatist militia leaders ordered the civilian evacuation over the border to Russia.

Denis Pushilin, head of the so-called Donetsk People’s Republic (DPR), said Ukrainian President Volodymyr Zelensky would order “soldiers to go on the offensive.”

In Moscow, Putin met with the authoritarian leader of Belarus, which is hosting tens of thousands of Russian troops on the Ukrainian border, and said he saw a “deterioration of the situation.”

But the Ukrainian command said the Russian-backed separatist forces had violated a ceasefire 53 times between midnight and 5:00 pm Friday.

Twenty children and 18 adults at a kindergarten in the government-held village of Stanytsia Luganska were lucky to escape almost completely unharmed on Thursday when an artillery shell struck the building.

– Russian ‘strategic’ forces –

The Russian defense ministry sent a chilling reminder of the stakes in any East-West confrontation when it announced that Putin would oversee Saturday’s “exercise of strategic deterrence forces… during which ballistic and cruise missiles will be launched.”

The air force, units of the southern military district, as well as the Northern and Black Sea fleets would be involved in the nuclear-capable missile tests.

Russia says that it will not back away from Ukraine unless Western countries agree never to allow Ukraine into NATO and to pull US forces back from eastern Europe, effectively creating a new version of the continent’s Cold War-era spheres of influence.

The conflict between the heavily armed pro-Russian rebels and Ukrainian government forces in the country’s east has already rumbled on for eight years, claiming the lives of more than 14,000 people and forcing more than 1.5 million from their homes.