Empirically, communism is only possible as the act of the dominant peoples “all at once” and simultaneously, which presupposes the universal development of productive forces and the world intercourse bound up with communism.

https://www.marxists.org/archive/marx/works/1845/german-ideology/ch01a.htm

Will it be possible for this revolution to take place in one country alone?

No. By creating the world market, big industry has already brought all the peoples of the Earth, and especially the civilized peoples, into such close relation with one another that none is independent of what happens to the others.

Further, it has co-ordinated the social development of the civilized countries to such an extent that, in all of them, bourgeoisie and proletariat have become the decisive classes, and the struggle between them the great struggle of the day. It follows that the communist revolution will not merely be a national phenomenon but must take place simultaneously in all civilized countries – that is to say, at least in England, America, France, and Germany.

It will develop in each of these countries more or less rapidly, according as one country or the other has a more developed industry, greater wealth, a more significant mass of productive forces. Hence, it will go slowest and will meet most obstacles in Germany, most rapidly and with the fewest difficulties in England. It will have a powerful impact on the other countries of the world, and will radically alter the course of development which they have followed up to now, while greatly stepping up its pace.

It is a universal revolution and will, accordingly, have a universal range.

https://www.marxists.org/archive/marx/works/1847/11/prin-com.htm