Airbus SE is poised for a grand entrance at the Paris Air Show, where the European planemaker could announce a record 500-aircraft agreement with Indian carrier IndiGo on the first day.

The proposed order, which would double the airline’s existing backlog, is for A320neo family aircraft, according to people familiar with the negotiations. IndiGo and Airbus are moving to announce the accord as early as Monday, said the people, asking not to be identified because the talks are private.

Airbus is also working to firm up talks with Saudi carrier Flynas Co. for a large narrowbody order that could become another marquee deal of the event alongside IndiGo, other people said, confirming negotiations previously reported by Bloomberg News. Negotiations for both transactions could still drag out and final number might change, the people cautioned.

Officials at Airbus, IndiGo and Flynas declined to comment.

Airbus Chief Executive Officer Guillaume Faury said on Friday that the show will demonstrate how the industry is returning “back to the good old times of excitement.” Even before the event, Airbus said it struck deals for 60 A320 family aircraft and 10 A350s from undisclosed customers, setting the pace for what stands to be a few busy days of orders.

Flynas said last year that it wants to raise the volume of its orders to 250 aircraft to become the leading low-cost airline in the Middle East. The company now has a fleet of about 50 aircraft, most of which are Airbus A320s. It also has about 50 orders pending with the European manufacturer.

IndiGo already has a backlog of about 500 planes as part of previous accord, including a 300-plane order in 2019. Reuters reported this month that IndiGo was close to placing a record deal with Airbus.

The airline is also working on a separate purchase of widebody aircraft, with both Airbus and Boeing Co. vying for a deal involving about 25 aircraft, other people said. Boeing may have the upper hand to secure that accord with its 787 Dreamliner, though negotiations remain in flux, said one of the people.

Boeing officials declined to comment.

A purchase by IndiGo would top a recent agreement by Air India to buy 470 aircraft from Airbus and Boeing as the country’s former flag carrier rebuilds its operations with a modern fleet under new ownership. India is one of the fastest growing aviation markets in the world with Indigo controlling close to 60% of domestic flying.