The EU says that under their visa-waiver agreement Washington must permit citizens from all 28 member countries to travel in the United States without visas.
But Washington refuses to do so for Bulgaria, Croatia, Cyprus, Poland and Romania until they meet the requirements of US law.
In Malta today, EU and US security officials said they "intend to step up efforts to improve security cooperation with a view to assisting (the five) in advancing more rapidly toward the fulfilment of the requirements" for a visa-waiver.