Question: Who wrote the play "...but the clouds..." starring Billie Whitelaw and Ronald Pickup?

Context paragraphs:
Leo the Last: Leo the Last is a 1970 British drama film directed by John Boorman, based on the play "The Prince" by George Tabori, starring Marcello Mastroianni and Billie Whitelaw.

Make Mine Mink: Make Mine Mink is a 1960 British comedy farce film directed by Robert Asher and featuring Terry-Thomas, Athene Seyler, Hattie Jacques and Billie Whitelaw.  The screenplay concerns a group of eccentric misfits who go on a spree, stealing mink coats for charity in a Robin Hood-style gang.  It was based on the play "Breath of Spring" by Peter Coke, and its sequels.  Seyer and Elspeth Duxbury reprised their stage roles from the London production of "Breath of Spring".

Charlie Bubbles: Charlie Bubbles is a 1967 British comedy-drama film starring Billie Whitelaw and Albert Finney, and also featuring a young Liza Minnelli.  It was listed to compete at the 1968 Cannes Film Festival, but the festival was cancelled due to the events of May 1968 in France.

Rockaby: Rockaby is a short one-woman play by Samuel Beckett.  It was written in English in 1980, at the request of Daniel Labeille, who produced it on behalf of "Programs in the Arts", State University of New York, for a festival and symposium in commemoration of Beckett's 75th birthday.  The play premiered on April 8, 1981 at the State University of New York at Buffalo, starring Billie Whitelaw and directed by Alan Schneider.  A documentary film, "Rockaby", by D. A. Pennebaker and Chris Hegedus records the rehearsal process and the first performance.  This production went on to be performed at the Annex at La MaMa Experimental Theatre Club, and, in December 1982, at the Cottesloe, Royal National Theatre, London.

Rough for Radio II: Rough for Radio II is a radio play by Samuel Beckett.  It was written in French in 1961 as Pochade radiophonique and published in "Minuit" 16, November 1975.  Beckett translated the work into English shortly before its broadcast on BBC Radio 3 on 13 April 1976.  Martin Esslin directed Harold Pinter (Animator), Billie Whitelaw (Stenographer) and Patrick Magee (Fox).  The English-language version was first published in "Ends and Odds" (Grove, 1976, Faber, 1977) as Radio II.

... but the clouds ...: ... but the clouds ... is a television play by Samuel Beckett.  Beckett wrote it between October–November 1976 “to replace a film of "Play" which the BBC had sent [him] for approval (and which he had rejected)” due to “the poor quality of the film”.  Donald McWhinnie directed Billie Whitelaw and Ronald Pickup.  It was first broadcast on 17 April 1977 as part of a programme of three Beckett plays entitled ‘Shades’ on BBC2.  It was first published in "Ends and Odds" (Faber) 1977.  An early title for the piece was Poetry only love.

Hotel Paradiso (film): Hotel Paradiso is a Metrocolor 1966 film released by Metro-Goldwyn-Mayer in Panavision.  It was directed by Peter Glenville and based on the play "L'Hôtel du libre échange" by Maurice Desvallières and Georges Feydeau.  The film allowed Alec Guinness to reprise the role he had played in the London West End theatre production of Hotel Paradiso, which opened at the Winter Garden Theatre, Drury Lane, London.  on 2 May 1956.  Guinness played alongside Martita Hunt (Angelique), Irene Worth (Marcelle), Frank Pettingell (Cot), Kenneth Williams (Maxime) and Billie Whitelaw (Victoire).  Douglas Byng also reprised his part from the stage play.

Footfalls: Footfalls is a play by Samuel Beckett.  It was written in English, between 2 March and December 1975 and was first performed at the Royal Court Theatre as part of the Samuel Beckett Festival, on May 20, 1976 directed by Beckett himself.  Billie Whitelaw, for whom the piece had been written, played May whilst Rose Hill voiced the mother.

Ghost Trio (play): Ghost Trio is a television play, written in English by Samuel Beckett.  It was written in 1975, taped in October 1976 and the first broadcast was on BBC2 on 17 April 1977 as part of the "Lively Arts" programme Beckett himself entitled "Shades".  Donald McWhinnie directed (supervised by Beckett) with Ronald Pickup and Billie Whitelaw.  The play’s original title was to be Tryst.  "On Beckett’s notebook, the word was crossed out vigorously and the new title "Ghost Trio" written next to it.  On the title page of the BBC script the same handwritten title change can be found, indicating that it must have been corrected at the very last minute."

Ronald Pickup: Ronald Alfred Pickup (born 7 June 1940) is an English actor who has been active in television and film since 1964.

Supporting paragraphs: ... but the clouds ... Ronald Pickup
Answer: Samuel Beckett.