A timely US visit during a perilous period for Ukraine

The dimension of Russia’s invasion is dramatically changing in its favour.

For almost 18 months, the front lines have been in a state of relative stalemate, with occasional, modest Russian gains.

But in the space of a week, overstretched Ukrainian troops are struggling to contain the most significant ground offensive since 2022 in the north-eastern Kharkiv region.

“Help is on the way,” is the US Secretary of State Antony Blinken’s message on a surprise visit to Kyiv. He comes during a perilous period for Ukraine.

Diplomatic visits by the country’s biggest military backer are not to be dismissed. The handshakes, working lunches and walkabouts typically bear fruit.

The approval of a $61bn military aid package in Washington is the biggest, juiciest one yet. But a month on, a fraction of it has arrived.

US officials stress some of the air defence systems, artillery and missiles are already in the eager hands of Ukrainian soldiers. Mr Blinken claimed, “they will make the difference on the battlefield”.

Perhaps those words would have carried more weight five days ago, when Ukrainian forces were just about hanging on across the 1,000km front line.

Now, they’re moving what few reserve troops they can to the Kharkiv region, where an estimated 30,000 Russian soldiers are continuing to advance from across the border.

They’ve taken at least 50 square miles (130 sq km) of once-liberated territory, in yet another cruel twist for this embattled province.