US defence secretary, Lloyd Austin, overnight announced $6bn in new military aid for Ukraine as Washington rushes to fill gaps left by months of stalled American assistance.

The new funding - the highest amount of Ukraine Security Assistance Initiative (USAI) aid sent to date - is set to include an array of munitions for air defence.

The package is the second this week, following another valued at $1bn that was announced just after the US president, Joe Biden, signed a much-delayed bill to provide new funding for Ukraine as it struggles to hold back Russian advances.