Despite a “unprecedented” surge of missile and drone assaults across the nation in recent weeks, Ukraine’s plans for a counteroffensive against Russian occupation are on track, its deputy defense minister told Reuters on Saturday.

According to Volodymyr V. Havrylov, Ukraine suffered numerous volleys of ballistic missiles in May, particularly in metropolitan areas such as the capital, Kyiv.

“Their primary goal is to stop our counter-offensive and target decision-making centers,” he said on the sidelines of Asia’s top security conference, the Shangri-La Dialogue in Singapore.

Havrylov called Russia’s heavy use of ballistic missiles in May a “last strategic resort” and noted that his country’s air defense systems had been “more than 90 percent effective” against the attacks.

For Russia “it was a huge surprise to find that the effectiveness of (their ballistic missiles) was almost zero against modern air defense systems, which we received from our partners,” he said.

The United States and Germany provided Ukraine advanced Patriot missile batteries this year. Ukraine had already received advanced shorter-range systems such as NASAMS and IRIS-T from Western partners.

Ukrainian President Volodymyr Zelenskiy said on Saturday his country was ready to launch a much-awaited counter-offensive. Havrylov said the missile barrages had not affected the timing.

“Nothing can stop our efforts, our desire, and our confidence that we’ll win this war,” he said.

Ukraine will “start the counter-offensive, with the ambition to liberate our territories this year,” he added.

Moscow calls the invasion, which began in February 2022, a “special operation”.

Havrylov declined to comment about recent drone attacks and border incursions into Russian territory, including some strikes that reached near Moscow.