From 1 May 2010 The Cuban government require all visitors to have travel insurance.
All of our flexible benefit insurance policies are underwritten by insurers at Lloyds of London and are acceptable to the Cuban authorities. Customers are advised to check this with their tour organiser for complete peace of mind.
You should carry the full policy wording available through your employer. You do not need anything from CSP. The named documents we issue do not prove that you have insurance - see article here.
We also recormmend that you read the article about proving insurance to the authorities.