Venezuelan Vice-President Nicolas Maduro made a surprise visit to his superior Hugo Chavez at the weekend.
President Chavez travelled to Havana to undergo his fourth round of cancer-related surgery on December 11.
The popular leftist, whose Bolivarian movement has dominated party politics in the Latin American country since 1999, called on his supporters to get behind Mr Maduro if another election is triggered by his failure to take up his office after re-election.
As Aslef's annual assembly of delegates begins in Edinburgh tomorrow the general secretary explains the challenges his members - and workers across the country - face