As the death toll from a US air raid on Pakistan climbs to 80, Islamabad has once again slammed Washington for attacks on its soil.

Pakistan's Foreign Office spokesman said such attacks undermine the country's sovereignty, adding that Islamabad made regular contacts with the US over the issue.

On Tuesday, some 80 people have been killed in what has been the deadliest US missile attack on Pakistani soil yet.

Pakistan Foreign Ministry spokesman Abdul Basit urged the US to stop such attacks as military operations to eliminate militants in tribal areas were well proceeding, a Press TV correspondent reported.

The missiles, that left nearly 100 people injured, hit the funeral of people who were killed earlier in the day during a similar strike in the volatile region.

The US has carried out at least 35 drone attacks on Pakistan's tribal areas, killing and wounding over 500 people over the past year.

RZS/MMN