  We propose a non-associative phase space algebra for M-theory backgrounds
with locally non-geometric fluxes based on the non-associative algebra of
octonions. Our proposal is based on the observation that the non-associative
algebra of the non-geometric R-flux background in string theory can be obtained
by a proper contraction of the simple Malcev algebra generated by imaginary
octonions. Furthermore, by studying a toy model of a four-dimensional locally
non-geometric M-theory background which is dual to a twisted torus, we show
that the non-geometric background is "missing" a momentum mode. The resulting
seven-dimensional phase space can thus be naturally identified with the
imaginary octonions. This allows us to interpret the full uncontracted algebra
of imaginary octonions as the uplift of the string theory R-flux algebra to
M-theory, with the contraction parameter playing the role of the string
coupling constant $g_s$.
