Only 65 per cent of the missiles launched by Iran earlier were intercepted by the Israeli air defence system versus almost 90pc the the day before, a senior intelligence official in Israel told NBC News.

“Iran still has very advanced missiles, and they are making use of them,” said the former top-level Israeli intelligence official, who still receives daily government briefings.

The official, who is not authorised to speak publicly because of the sensitivity of the information, said that faster Iranian missiles launched in the last few days have also given Israel less time to prepare before the projectiles approach their intended targets.

A longtime observer of Iranian activities in the region, the official added that the regime, despite having suffered significant leadership losses when Israel launched its surprise attack last week, still has missile stockpiles that could sustain their retaliatory strikes for long stretches, describing their approach as “strategic patience.”