Scorpio Tankers has signed a deal with an undisclosed company to buy four medium-range (MR) tankers being built at South Korea’s Hyundai Mipo Dockyard (HMD) for $36.5m each.

The vessels are identical to Scorpio ‘s STI Amber-class vessels on order at HMD and are scheduled to be delivered between June and September 2013.

According to the company, the deal, which is subject to final documentation, will be concluded by novation of the current shipbuilding agreements.

Scorpio has also exercised options with HMD to build two ice class-1A handymaxes at a cost of $31.5m each, with expected delivery in the third quarter of 2014.

The deal is an exercise of options from the company’s previous contracts with HMD and includes fixed-price options for additional units.

Scorpio currently has 39 newbuilding product tankers on order with HMD, SPP Shipbuilding , Hyundai Samho Heavy Industries (HSHI) and Daewoo Shipping and Marine Engineering (DSME ), including 23 MR, eight Long Range 2 (LR2) and eight Handymax ice class-1A tankers.

Out of the total units, five new vessels are scheduled to be delivered by September 2013, while the remaining 34 are expected to be delivered by the end of 2014.