Argentina's return to the MotoGP World Championship was re-confirmed at the end of Thursday's opening day of testing at the Termas de Rio Hondo circuit.

The new circuit, 1,100km north east of Buenos Aires, will host MotoGP from 2014 'until at least 2016'.

Argentina's last Motorcycle Grand Prix was held in 1999, with the South American country due to return to the calendar this season.

However the event was postponed after the Spanish government advised any teams or riders sponsored by Repsol not to travel due to "safety reasons". That warning was lifted late last year.

The date of next year's Argentine round is yet to be made official, but this year's cancelled grand prix had been pencilled in for mid-April, between Qatar and Texas - a tie-up with Texas making sense from a logistic point of view.

While it is possible the MotoGP calendar could rise from 18 to 19 rounds, Argentina may well replace Indianapolis, which is openly considering dropping off the schedule after this August's grand prix.

Six riders - four from the MotoGP class and two from Moto2 - made the long trip down into the southern hemisphere to try out the circuit, whilst also gathering bike set-up and tyre data. Bridgestone expects the circuit to be the harshest event of the year on tyres, and has brought a variety of symmetric and asymmetric slicks to test.

A further aspect of the test, as explained by Dorna's Javier Alonso, was to check the safety of the track, the marshals, and the general operation of the event in preparation for next year. Alonso was happy with how things had gone so far and impressed with the circuit.

LCR Honda's Stefan Bradl ended the day as the fastest rider with a time just over the 1m 44s mark, after initial times had been in the 1m 57s. GO&FUN Honda Gresini's Alvaro Bautista left it late to go second (+0.343s), ahead of Monster Yamaha Tech 3's Cal Crutchlow (+0.982s).

Avintia Blusens' Hector Barbera is the sole CRT representative on his FTR Kawasaki (+3.704s), with the Spaniard also able to gather valuable data for the Magneti Marelli electronics for the coming year's race. He ended the day in fourth.

Of the Moto2 riders, Tuenti HP 40's Tito Rabat headed the first day on his Kalex machine in the mid 1m 48s as he not only searches for a benchmark-time for the class, but also goes through the motions with the Dunlop tyres. Compatriot Nico Terol, on the Mapfre Aspar Team Moto2 Suter machine, lapped just over 1.5s slower.

The second and final day of testing will begin at 10am on Friday morning.