Robert Walker

Robert Walker was the Parliamentary Secretary to the United Kingdom's Minister for the Armed Forces. (PROSE: Doctor Who and the Sea-Devils, Where the Heart Is)

He was sent to the Royal Navy base HMS Seaspite on Fortress Island to deal with the Sea Devils. He ordered Captain John Hart to launch an attack on their base, just as the Third Doctor was trying to negotiate peace with them. (TV: The Sea Devils)

He later presided at a meeting that, among other things, voted to cut off the UK's funding of UNIT. (PROSE: Where the Heart Is)

Behind the scenes
The character was only referred to as "Walker" in The Sea Devils, but his first name Robert was given in the story's novelisation and was later used in the short story Where the Heart Is.