By Daniel Lak BBC correspondent in Delhi

The American ambassador to India, Robert Blackwill, says there has been an increase in Islamic militant infiltration from Pakistani-administered Kashmir as India holds elections in the portion of Kashmir under its administration.

America is clearly worried that the remaining stages of the Indian Kashmir elections could produce more violence...

Speaking in a recorded interview to be broadcast on Thursday night on Indian satellite television, Mr Blackwill calls on President Musharraf of Pakistan to live up to promises to curb infiltration as part of US-brokered efforts to ease tensions between India and Pakistan.

By the standards of traditional diplomacy in the sub-continent, these are strong public remarks by the American ambassador.

Mr Blackwill told Indian television news channels that Islamic militants were again infiltrating in increasing numbers from Pakistani- to Indian-administered territory in Kashmir.

This, he said, came after a decrease in June and July.

America 'worried'

India has been saying for weeks now that Pakistan is sending more militants in to disrupt the election process in Kashmir, despite a commitment by President Musharraf earlier this year to stop infiltration completely.

Pakistan has called the Indian Kashmir elections a sham, but Mr Blackwill says this was not Washington's view and he called for the two countries to start talking about peace once the voting was over.

Ambassador Blackwill : Calling Pakistan to live up to promises

The Indian Government will be pleased with the ambassador's words - Pakistan of course will be dismayed.

Islamabad denies that it has direct influence over militant groups, but not many diplomats in the region believe that.

The issue of infiltration became crucial earlier this year as India reacted angrily to a series of Islamic militant attacks, including one on parliament in Delhi last December.

The resulting build-up of troops brought the sub-continent to the brink of war and although soldiers remain deployed, tensions have lowered considerably.

America is clearly worried that the remaining stages of the Indian Kashmir elections could produce more violence and Ambassador Blackwill is warning Pakistan that Washington takes a dim view of that.

Terrorism in any form, he says in his interview, can never be justified as a political instrument.