RIVNE, Feb 16 (Reuters) - Ukrainian President Volodymyr Zelenskiy and military observers from NATO member states including Britain and Poland looked on as the country's armed forces carried out drills in western Ukraine on Wednesday.

Tanks fired shells and drove across bumpy fields while soldiers trained with Javelin anti-tank missiles near the city of Rivne.

The drills, part of the Zametil 2022 (Blizzard 2022) exercises, were carried out as Ukraine prepared for a possible military attack from Russia, which has massed more than 100,000 troops near Ukraine's borders.

Colonel Andriy Melnik, one of the commanders at Rivne training ground, said the troops practiced with a wide range of weapons.

"We are using the whole spectrum of weaponry available to the commanders of the land troops -- artillery, tanks, armoured vehicles, anti-tank rockets, guns," he said.

Hanna Malya, the Ukrainian deputy defence minister, said the exercise proved the readiness of the Ukrainian armed forces.

"We are fully ready to defend our state and we will defend it," she said after observing the drill.

The United States and NATO said Russia was still building up troops around Ukraine on Wednesday despite Moscow's insistence it was pulling back, questioning President Vladimir Putin's stated desire to negotiate a solution to the crisis.

Russia denies planning any invasion of Ukraine.