"Support by elements of Pakistan's military and intelligence services for violent extremist organisations targeting India has the potential to result in military confrontation that could rapidly escalate to a nuclear exchange," James Miller said in written answers submitted to the Senate Armed Services Committee during a confirmation hearing for the post of Undersecretary of Defence for Policy.
He noted that India and Pakistan have "a long and complex history characterised by animosity, mistrust, and conflict."
Current efforts at dialogue through a renewed comprehensive dialogue have yielded few concrete results on the core security issues, especially regarding the resolution of territorial disputes, Miller said.
However, the efforts have increased people-to-people exchanges and trade relations between the two nations, and have provided each side greater insight into the other's positions, he said.
"Although progress is slow, the trajectory is positive and offers the promise of increased confidence-building measures," Miller said.
He said India's actions in South and Central Asia generally align with US goals: increasing economic growth and political stability through strengthened democratic institutions, and developmental assistance to help prevent radicalisation.
Regional stability ultimately depends on cooperation among India, Pakistan, and Afghanistan, he asserted.
"Transparency in the India-Afghanistan and Pakistan-Afghanistan bilateral relationships is critical to reduce misunderstanding and mistrust between India and Pakistan," he told the lawmakers.
"The ongoing transition of lead responsibility for security in Afghanistan to Afghan forces, and the strategic partnerships Afghanistan has been negotiating with the United States and other international partners are important steps toward demonstrating long-term commitment of the international community, addressing conditions that create uncertainty, and stabilising the region," Miller said.