"Blow up the topmast" - what does it mean?

On June 10, 1946, Hatim A. Alavi wrote to Jinnah {Quaid-I-Azam Mohammad Ali Jinnah Papers,  Volume XIII, Cabinet Mission's Parleys for Shaping India's Future, 1 April-31 July 1946, Editor: Z.H. Zaidi, #161, pages 235-237}

You said at our Council meeting [1] that we can work on the two decks, provincial and group, and blow up the topmast.  Will that be possible since the complete constitution is subject to ratification by the British Parliament?

[1] Held at Imperial Hotel, New Delhi, on 5 & 6 June 1946

What does "blow up the topmast" mean?  Whatever it was, Alavi seemed doubtful that the British would approve.

PS: The Council is the All India Muslim League Working Committee.