India is expected to announce its new ambassador to the United States soon to succeed incumbent Ronen Sen, who is set to return on completion of his tenure in March.

Sen, who was recently embroiled in a controversy over his headless chicken remark in an interview with rediff.com, is unlikely to get a further extension, sources said on Monday.

The 64-year-old diplomat, who has been in Washington since August 2004, is also not keen on getting an extension and is understood to have conveyed this to the government.

The nearly four-year tenure of Sen was marked by growth in Indo-US relations, with the civil nuclear deal being the highlight.

The ambassador was in a soup in the middle of last year when he reportedly equated Indian Parliamentarians with 'headless chicken'.

The remark angered the MPs, who sought his recall. Though he apologised and insisted that the comment was not against Parliamentarians, Sen was summoned by the Privileges Committees of Lok Sabha and Rajya Sabha.

Significantly, Sen's tenure is ending at a time when the two countries are making efforts to operationalise the nuclear deal.

Commenting on Sen's departure from Washington, US envoy to India David Mulford said he had been an 'effective ambassador', who served New Delhi's 'interests very well.'