* Orders 3 777-300ER for Swiss, 6 used A320 for Eurowings
* No new planes for unit Austrian Airlines
* Planes worth 1 bln euros at list prices
* CEO says low oil price makes older planes more efficient (Adds comments from CEO and CFO, Austrian planes decision)
FRANKFURT, March 12 (Reuters) - Lufthansa has ordered three new Boeing 777-300ER aircraft for Swiss and six used A320 planes for Eurowings, it said on Thursday.
The planes are worth 1 billion euros ($1.06 billion) at list prices, Lufthansa said, taking the total amount of aircraft the group has on order to 272 aircraft with a list price of 38 billion euros.
However, the group is holding back on investment in new planes, it said on Thursday, due to the low oil price making older planes more efficient.
Lufthansa Finance Chief Simone Menne said the group had always planned to order the 777 for Swiss but had reduced the number of planes.
Chief Executive Carsten Spohr said the order for just nine planes showed how the group was limiting investments, adding that it had delayed some A350 orders and some freighters.
He also said Lufthansa had decided not to invest in new planes for the Austrian Airlines unit but instead to shift 16 Embraer aircraft from its smaller CityLine unit.
“The fuel going down allows us to extend old aircraft without having similar disadvantages as in the past, at the same time as reducing investment numbers,” he told analysts.
Lufthansa said it would limit annual investment to 2.5 billion euros in 2016 and 2017 after 2.9 billion euros in 2015.
The new 777s will be delivered to Swiss from 2017 onwards. The carrier is already expecting six of the planes to be delivered from 2016.
The A320s will be delivered to Eurowings beginning in 2016 and will be used on short-haul routes.
$1 = 0.9431 euros Reporting by Victoria Bryan; Editing by Georgina Prodhan