AS many as 40,000 Russian troops are massing on the country's border with Ukraine - prompting fears of a new military invasion.

The Pentagon has identified eight staging areas dotted along the border, suggesting Russian strongman Vladimir Putin is preparing for new incursions.

3 Fears are growing that Vladimir Putin is planning new excursions into neighbouring Ukraine Credit: Getty Images

Among the units deployed to the area are armoured vehicles, tanks and fighter jets.

Navy Captain Danny Hernandez told the Washington Free Beacon that the exercises were being closely monitored.

He said: "We are extremely concerned about the increasing tensions near the administrative boundary between Crimea and the rest of Ukraine.

"We urge both sides to avoid provocative steps or rhetoric that could escalate the situation."

related stories PUTIN'S PURGE Shock as Vladimir Putin’s sacks his Chief-of-Staff after years in the Russian President’s inner circle 'BRITS NO MATCH FOR RUSSIANS' Red alert as Russia stocks up on secret weapons after testing them in war against Ukraine Pictured Red Zeppelin Vladimir Putin is planning to build this huge £23million airship and it's bigger than a Boeing 747 KREMLIN THREAT Putin orders war games off Crimea after accusing Ukraine of trying to stir up conflict Pictured INSIDE THE WAR ZONE Horrifying images reveal extent of fighting in Syria's war torn Aleppo as Russia teams up with Iran PUTIN IS WATCHING US The tyrant's Russian spy planes are flying over Britain – and the MoD is absolutely fine about it

Officials told the publication similar movements were seen before Vladimir Putin carried out his deceptive annexation of the Crimea.

Such manoeuvres have reduced the "warning time" available to the US if he decides to launch another attack.

In June it was reported Russia was constructing an army base near the border which it considers to be a new front line with NATO.

A Reuters reporter who visited the Russian town of Klintsy, about 30 miles from Ukraine, saw a makeshift army camp, large numbers of newly-arrived servicemen and military vehicles.

3 Russian armoured personnel carriers travel through the Crimea during its 2014 annexation from Ukraine Credit: Reuters

3 New army manoeuvres in the area have sparked fears of another military engagement Credit: Getty Images

Two soldiers in camouflage gear who were manning a checkpoint in a forest turned the reporter away, saying they were guarding a "special military site".

Over the past 12 months, Russia has continued carrying out military manoeuvres in the area while NATO carries out exercises in its eastern flank.

Confrontational rhetoric from both sides has also intensified to levels not seen since the Cold War.

We pay for your stories! Do you have a story for The Sun Online news team? Email us at tips@the-sun.co.uk or call 0207 782 4368.