The charters are part of deals announced today that could total NOK 1.2bn ($200m) if all options are exercised.

The Norwegian offshore vessel owner told the Oslo Stock Exchange that the undisclosed charterer will take the units for a fixed term of three years.

Each charter will also involve a two one-year options.

The 6,500-dwt multipurpose support vessels are due to be delivered in 2014 and 2015 from Norway's Kleven Maritime.

Meanwhile,