UKRAINE: Ukrainian President Volodymyr Zelensky has cancelled all trips abroad in the coming days in light of the advancing Russian offensive in the Kharkiv region, his spokesman Serhiy Nykyforov said on Wednesday.

Zelensky was to visit Spain and Portugal at the end of the week.

Russia began a ground and air assault on Ukraine's second city Kharkiv, in the north-east and the surrounding region last week.

In what analyst describe as one of the most perilous moments for Kyiv in the war, Moscow's forces have been able to capture several villages as they continue to bombard Kharkiv with missiles.

Worries are mounting that Russia is using the wave of attacks on the city to possibly lay the groundwork to capture Kharkiv.

The military leadership in Kyiv - struggling with a lack of weapons, ammunition and soldiers - said earlier on Wednesday that troops were being withdrawn from some Kharkiv positions.