Although the decision to shift National Security Adviser M.K. Narayanan out of the Prime Minister’s Office and into a vacant Raj Bhavan has been taken, the government has yet to decide on his successor or the State to which he will go as governor.

One thing, however, is certain: the role and office of the NSA, which is still very much a work in progress as far as the wider architecture of governance is concerned, is likely to focus more exclusively on the problems of diplomatic engagement rather than internal security management.

This shift in emphasis, which began when P. Chidambaram took charge of the Home Ministry in 2008, will both influence — and be influenced by — the choice of the next NSA.

According to informed sources, the former Foreign Secretary Shiv Shankar Menon is the clear front-runner. Other potential contenders are either otherwise engaged — Special Envoy Shyam Saran is too valued by the Prime Minister for his work as climate change envoy — or, like the former Indian ambassador to the U.S., Ronen Sen, slated to make the gubernatorial cut.

With Manmohan Singh travelling to Kolkata on Saturday, the capital was awash with rumours of the Prime Minister seeking West Bengal Chief Minister Buddhadeb Bhattacharya’s concurrence for sending the NSA as governor to his State. However, a senior leader of the Communist Party of India (Marxist) told The Hindu on Friday that the party would oppose Mr. Narayanan’s name for Bengal. “He is well-known as a hatchet man for the Congress,” the leader said. “If they want to send him somewhere else, they are welcome. We will not agree to him coming to Bengal.”

Other names in the ring for governorships are the former Union Home Minister, Shivraj Patil, senior Congress leader Mohsina Kidwai, whose Rajya Sabha term ends in June, Urmilaben Patel, wife of the former Gujarat Chief Minister, Chimanbhai Patel, Krishna Sahi, the former Union Minister in the Narasimha Rao government from Bihar and Santosh Mohan Deb, the former Union Minister from Assam.

The Congress core committee, including the Prime Minister, party president Sonia Gandhi, Mr. Chidambaram and party leader Ahmed Patel, met on Friday evening to finalise a decision.

Besides West Bengal, the Centre will appoint governors to Andhra Pradesh, Punjab, Rajasthan and Maharashtra.