An attack on tourists in India's Himalayan territory of Kashmir this week sparked a new crisis between nuclear armed South Asian neighbours India and Pakistan, with New Delhi blaming militants with "cross-border linkages" for the killings.

Relations between India and Pakistan are cratering following a deadly attack in the disputed Himalayan region of Jammu and Kashmir that left more than two dozen tourists dead.

US State Department spokesperson Tammy Bruce dismissed a Pakistani journalist's question on India-Pakistan border tensions, reiterating that US officials have already made their positions clear on the matter.