The former boxer said he was left 'speechless' by Germany over their refusal to give substantial military aid and drop their support for the Nord Stream 2 gas pipeline while Russian troops continue to amass on Ukraine's border.
He told Bild: 'The behaviour of the German government leaves me speechless.
'The defence ministry apparently hasn't realised that we are confronted with perfectly equipped Russian forces that can start another invasion of Ukraine at any time
'What kind of support will Germany send next. Pillows?'
Kiev mayor Vitali Klitschko has branded Germany's latest offer of 5,000 helmets to Ukraine a 'joke'
A Strela-10 anti-aircraft missile system of the Ukrainian Armed Forces fires during anti-aircraft military drills today
Germany says it has long refused to export arms to conflict zones and is declining Ukraine's appeals for weaponry
Earlier this week, Klitschko accused Germany of 'betraying' his country for their 'failure to provide assistance and betrayal of friends' as tensions reach boiling point amid increasing fears of an imminent invasion.
Germany says it has long refused to export arms to conflict zones and is declining Ukraine's appeals for weaponry.
Germany is also heavily dependent on Russia for its supply of gas, with up to 40 per cent of the EU nation's gas imports coming via Russian pipelines.
The ex-heavyweight champion wrote in Bild: 'There is huge disappointment in Ukraine that the federal government is sticking to Nord Stream 2 and that it does not want to supply defence weapons.
'This is failure to provide assistance and betrayal of friends in a dramatic situation in which our country is threatened by Russian troops from several borders.'
Members of Ukraine's Territorial Defence Forces, volunteer military units of the Armed Forces, train in a city park in Kiev
A service member of the 14th Separate Mechanised Brigade of the Ukrainian Armed Forces takes part in anti-aircraft military drills today
His comments come as Ukraine's foreign minister Dmytro Kuleba said the number of Russian troops deployed along his country's border was not enough for a major attack.
'The number of Russian troops amassed along the border of Ukraine and occupied territories of Ukraine is large,' Kuleba said, referring to Moscow-annexed Crimea and separatist-controlled parts of eastern Ukraine.
He told reporters that 'it poses a threat to Ukraine' but is 'insufficient for a full-scale offensive'.
Kuleba added that Russia is still capable of building up its deployments to 'a sufficient level' over time.
His comments are in contrast to those of Kyiv's Western allies, including the US, who have warned that Russia may attack at any moment.
Russian Foreign Minister Sergei Lavrov (left) and State Duma Speaker Vyacheslav Volodin (right) talk before a parliamentary session today
A serviceman holds his machine-gun in a trench on the territory controlled by pro-Russian militants in Slavyanoserbsk
The US has responded to the growing concerns by urging its citizens in the ex-Soviet country to 'consider departing now'.
'The US embassy urges US citizens in Ukraine to consider departing now using commercial or other privately available transportation options,' the embassy said in a statement, warning that the security situation 'can deteriorate with little notice.'
US officials are convinced Putin intends to use force by mid-February, according to Deputy Secretary of State Wendy Sherman.
She said today: 'I have no idea whether he's made the ultimate decision, but we certainly see every indication that he is going to use military force sometime perhaps (between) now and the middle of February.'
The Kremlin has repeatedly denied it has any such designs, but the US and its NATO allies are worried about Russia deploying an estimated 100,000 troops near Ukraine and launching a series of sweeping military maneuvers.
An American shipment of 300 anti-tank Javelin missiles worth $50million landed in Kiev overnight, the third batch of a $200million military aid package designed to bring death and destruction to Russia's forces if Putin invades
As part of the drills, motorized infantry and artillery units in southwestern Russia practiced firing live ammunition, warplanes in Kaliningrad on the Baltic Sea performed bombing runs, dozens of warships sailed for training exercises in the Black Sea and the Arctic, and Russian fighter jets and paratroopers arrived in Belarus for joint war games.
Elite paratroopers have also been moved close to the border for the first time amid fears of an operation to seize the capital of Kiev.
A train with the troops and their equipment was spotted moving west towards the potential warzone and appears to be the 217th Guards Parachute Regiment of the 98th Airborne Division.
The deployment was seen passing through Russia's Bryansk region which borders both Ukraine and Belarus, as shown in a video posted on TikTok.
An analysis by respected independent Russian researchers known as the Conflict Intelligence Team (CIT) indicates the tarpaulin-covered armoured vehicles in the video are BMD-4M airborne combat vehicles and BTR-MDM airborne armoured personnel carriers.
Russia has been massing forces on Ukraine's border for months, sparking fears that an invasion is imminent - and is now sabre-rattling across Europe including a new set of naval drills due to take place near Ireland (left)
'The train includes five passenger carriages, which can carry more than