A masterful character actor who was in the first London season of the Royal Shakespeare Company in 1961 and who became a familiar face in countless television sitcoms and serials, notably as a core cast member in The Duchess of Duke Street in 1976.

In The Duchess, he played the enigmatic hall porter Mr Starr, never without his squeaky boots or little dog, Fred - a performance that led to comedy stints with Frankie Howerd, Roy Kinnear and Dick Emery. He was a Cockney dad in Central's The Other 'Arf (1980), opposite Lorraine Chase's Twiggy-like model, and also appeared in the BBC's Sitting Pretty (1992), with Diane Bull as "the Jackie Onassis of Bethnal Green".

Cater was a perfectionist, proud of his craft. He said that if you could not cross a stage with a cup of tea, do a half-trip, a double-take on the non-existent pothole and finish the un-spilt cuppa on the other side, you should find something else to do for a living. His timing was immaculate.

He was born in Hendon, north London, into a family of florists, though his mother was a violinist in the Piorinos, a musical dance band trio. At the age of four, John was enrolled at the Jean Boggan school of dance and, with the outbreak of the second world war, was evacuated with his entire Hendon prep school to Devon. He completed his education at Shebbear college, near Bideford, before going on to Rada in 1948.

This was interrupted by national service in the Royal Army Educational Corps, but on graduation he was employed at the Dundee Rep by Herbert Wise, a lifelong friend with whom he later appeared in three episodes of the BBC's I, Claudius, as Narcissus (1976).

Rep and summer seasons followed at Nottingham, Guildford, Aberdeen, Edinburgh and Cork before he joined Peter Hall's first London RSC at the Aldwych, appearing in The Duchess of Malfi, Ondine with Leslie Caron and John Whiting's The Devils.

These were heady times, made headier by falling in love with his fellow RSC actor Wendy Gifford, whom he married in 1963. A modest career in films was launched with support roles in Alfie (1966), Loot (1970) and a pair of horror movies which starred Vincent Price, the Abominable Doctor Phibes (1971) and Doctor Phibes Rises Again (1972).

His first television appearance was in a 1949 play about the French resistance, broadcast live from Alexandra Palace. Small-screen credits included the landmark Jean-Paul Sartre adaptation Road to Freedom (1970) and snowballed in series such as The Bill, Crossroads, Minder, Casualty and Midsomer Murders. His last BBC series was last year's ill-fated archaeology drama Bonekickers; his last film was Alien Autopsy (2006), starring Ant and Dec.

Cater's theatre work picked up again with John Wells's hilarious satire Anyone For Denis? at the Whitehall in 1981 in which he played Denis Thatcher's bankrupt buddy Maurice Picarda. He rejoined the RSC in 1984 to play in Judi Dench's Mother Courage, Corbaccio in Volpone and Kit Carson in William Saroyan's The Time of Your Life.

More recently he was at the Almeida in two Jonathan Kent productions, David Hare's version of Pirandello's Rules of the Game in 1992 as a doctor fussing over what one should wear for a duel, and Gangster Number One, starring Peter Bowles in 1995, as a small-time thief. He also featured as a spectacularly suspended Justice Shallow in Terry Hands's beautifully autumnal Merry Wives of Windsor at the National, also in 1995.

Cater loved music of all kinds, especially Ravel, Debussy and Mahler, and was not only an avid jazz fan but an accomplished musician himself, playing jazz piano as well as trombone, harp and guitar.

He had a rare blood disorder, haemochromatosis, but his life was not seriously affected until arthritis set in. He died of liver cancer. He was survived by his wife Wendy as well as his daughters Harriet and Emma,