Norwegian Air plans to serve new destinations in South America from London, prompted by strong demand for flights to Buenos Aires which begin this week as it ramps up its budget operation on long-haul routes.

Norwegian's South American expansion plans could open up a new front in the transatlantic travel battle between budget carriers and traditional long-haul players such as British Airways parent IAG, Air France-KLM and Delta .

"I can assure you that the UK will get more routes into South America than Buenos Aires," CEO Bjorn Kjos told a press conference in London on Tuesday.

Norwegian also announced that from 2020 it would use eight new single-aisle Airbus A321neoLRs, currently undergoing test flights including across the Atlantic, to fly from Britain to cities on the U.S east coast and in the mid-west, keeping up the pressure on established airlines.

Transatlantic routes are among the industry's most popular and profitable and the presence of Norwegian and other low-cost airlines on routes from Europe to the United States has already prompted traditional long-haul players to set up new operations or change pricing structures.

Traditional players could also face competition from Norwegian on routes from London to Tokyo, Shanghai and Beijing, if the carrier is given rights to fly across the Siberian corridor in Russia, the shortest route to Asia, Kjos said.

Norwegian, Europe's third-largest budget airline after Ryanair and easyJet, needs permission under a deal with Russia before it can access this route.

In the meantime, Norwegian, which is due to announce fourth-quarter results on Friday, is focusing on South America.

"We're being invited to set up long-haul routes into (south American) countries and domestic operations into the same countries, like a copy cat of what we are doing in Argentina," the CEO said.

Norwegian's first flight to Buenos Aires from London Gatwick takes off on Wednesday. Tickets cost from 259.90 pounds (US$361), compared with British Airways flights which can cost around 1,900 pounds according to price checking website Skyscanner.