Ducati has called MotoGP's late decision to change its testing restrictions "disrespectful", after the Italian manufacturer had to alter is arrangements to suit the new rules.
It was announced in October that for the 2018 season only three of the five test days allocated to race riders can take place at tracks where MotoGP races have yet to be held.
In addition, test riders are now only permitted to test at three nominated test venues.
The rule change comes in response to teams using test days on a track prior to a grand prix to set up their bikes in preparation for the weekend.
"In principle, Ducati agrees with the idea," said Ducati's sporting director Paolo Ciabatti.
"What we didn't agree was the decision being taken one month before the beginning of a new season.
"We think that it was disrespectful to the companies that had already planned testing activities and also the allocation of bikes between factory teams and satellite teams.
"We were against the change decided in Japan when the new season would begin after one month."
Ducati says it had to make late changes to its testing plans as a result of the new regulations.
Factory riders Jorge Lorenzo and Andrea Dovizioso were sent to Jerez in November - not the original plan - according to Ducati general manager Gigi Dall'Igna.
"I think that the new rules are absolutely reasonable," he said.
"I agree with the principle of the rule but I am not agreed with how this rule will be implemented.
"Above all regarding the time, I am completely against it because we planned all the next year's tests - in November we planned how and when the riders have to test the new bike.
"The [initial] programme was that Dovi and Jorge had to test the new bike [at Valencia] in the test after the race, and [Danilo] Petrucci had to test with [Michele] Pirro in Jerez at the end of November.
"Now we have to change this completely because Jerez is not our test track anymore, so Pirro cannot test there and also Jorge and Dovi cannot test five days next year so we have to use the span of two days in November."
In addition to the restrictions for next season, the number of official pre-season tests will be reduced from three to two in 2019, in part due to the expansion of the calendar to 19 races in '18.