Martins was speaking at a New Age business breakfast briefing in Fourways, Johannesburg, on Friday.
He said the shipping sector had great potential.
"Ships only came to South Africa to load or offload and thereafter they go back to their respective countries. That needs to change."
On road safety, Martins said it was unacceptable that motorists obeyed traffic rules only when law enforcement officers were on the road.
"It cannot be correct that we only do right when a policeman is at a corner. We cannot put a policeman on every corner."
During the festive season 18 000 traffic officers were deployed on national roads.
Deputy Minister Sindisiwe Chikunga said road users had to change their attitude towards road rules.
"When you overtake on a barrier line you are committing a crime, you are a criminal."
On e-tolling, Chikunga said the public needed to understand that the toll in Gauteng was no different to other tolls on national roads in other provinces.
"The only difference is that in other tolls you pay manually and in this one payment is by electronic means. If you drive on the N3 to Durban you stop and pay at toll plazas."
She said it would be unfair to pass the toll fee into fuel price increases as people who would not be using the roads would then also be charged.
She said manual payment could not be used in Gauteng due to the number of vehicles using national roads in the province.
Martins said people protesting against the e-toll had the right to protest but not the right to destroy infrastructure. – Sapa