Low-cost airlines IndiGo and SpiceJet have petitioned the Supreme Court, challenging an ultimatum by the Meghalaya High Court directing them and authorities to decide on the date of launch flights from Shillong by holding a meeting within December 15.The High Court had ordered the aviation regulator DGCA, aviation ministry and the airlines such as IndiGo, Jet Airways, GoAir and Vistara to finalise plans to begin operations. The Supreme Court has agreed to hear the petition by the airlines on Thursday.The Meghalaya High Court took up the matter suo moto; there was no petition filed to this effect. The case has been taken up by a two-judge bench led by Chief Justice of the Meghalaya High Court Mohammad Yaqoob Mir.The court has been nudging airlines through the aviation ministry since January to launch flights to the Umroi airport in Shillong. "It was found desirable" to put the airlines on notice because "it appears that the airlines have taken the matter very lightly and not bothered to advance the public cause."Though such an order is unusual — airlines decide flight routes based on business viability, with the exception being remote destinations classified by the government — the order is not without precedent.In April 2016, the Supreme Court itself gave a similar ultimatum to authorities to launch flights to Shimla. The court was ostensibly perturbed by the lack of air connectivity to the Himachal Pradesh capital and gave May 4 as the deadline to begin operations. Government-owned Air India, which is struggling to stay aloft, now flies to Shimla.The Meghalaya High Court is using the route dispersal guidelines, which force them to deploy flights to remote areas — routes to Shillong and other parts of the North East are classified as Category II A — to push them to launch operations.IndiGo and SpiceJet have informed the Supreme Court that they cannot begin commercial operations from Shillong because the airport there lacks infrastructure facilities to support commercial operations of large aircraft.IndiGo has the smaller ATR planes and SpiceJet the Q400s in their fleet. Airlines prefer to use smaller planes in short routes so that the operation makes business sense.A spokesperson for IndiGo said the airline received the order dated December 7, 2018 . SpiceJet did not comment for this article.The Meghalaya court had warned that it would summon the chairman of Air India, the aviation secretary and chief of the Airports Authority of India, which manages the airport, if they fail to finalise plans.