Thousands of dollars have been raised by the public to send two West Australian World War II veterans to Canberra for a lunch with the Australian and British prime ministers.

Brothers Eric and Murray Maxton were told they would have to pay their own way to the event, being thrown in honour of Australian airmen who fought in Bomber Command.

Radio listeners called in to pledge almost $7,000, as well as offers of car hire and accommodation within a half-hour period on Tuesday morning after the brothers' plight was featured on 666 ABC Canberra.

Qantas will fly the brothers, their carers and three other immediate family to Canberra and has told the group it will refund the cost of all of their tickets, which they had booked and paid for.

Virgin Australia also offered to pay for return flights for the pair after being contacted by the Prime Minister's office.

Opposition Leader Bill Shorten contacted Virgin Boss John Borghetti early on Tuesday morning to ask for their assistance.

Murray, who is 94, told 720 ABC Perth how grateful he was for the offers of help.

"We didn't really want the public to pay our way," he said.

Murray Maxton (centre) and Eric Maxton (right) in flying days during WWII ( Supplied: Maxton family )

"We could've afforded it but it would have been a fair expense."

Murray said he was not asking for charity but appreciated what had happened.

"Australians are wonderful people, they seem to help each other when there's a bit of a crisis on," he said.

"We never asked for charity but we wanted to put [Department of] Veterans' Affairs into gear a bit."

He said he was looking forward to meeting the Prime Minister.

"It's going to be a wonderful few days there in Canberra," Murray Maxton said.

Eric, 90, and Murray were invited by Prime Minister Tony Abbott to join him and British prime minister David Cameron for the lunch on Friday.

Acting Prime Minister Warren Truss said he was delighted the brothers would go to the lunch.

"People usually pay their way when they go to lunch but these are special people, these are people who will contribute to the occasion," he said.

Brothers never should have been put in this position: RSL

Returned Services League national secretary John King said the brothers should never have been put in a position where they were left out of pocket to attend the lunch.

"I think at their advanced age, it could have been a simple act for the Government to have paid this," he said.

The ABC understands people have made pledges to the RSL.

RSL national president retired Rear Admiral Ken Doolan said he was delighted members of the public were trying to help the Maxton brothers.

"The RSL will do absolutely everything we can to support this and we're delighted to do it," he said.

Earlier this month the brothers were presented with the Legion of Honour by the French for their bravery, the first acknowledgement of their service by any government in 70 years.

Murray said receiving it had been an honour.

"It was a very humbling experience after all that time," he said.

"We're fairly old. If it had happened 70 years ago, we could have played up a bit and had a few beers."

Murray and Eric flew together in 460 Squadron in 1944, bombing Hitler's factories in Nazi Germany.

They were the only brothers to fly combat missions in the same aircraft, a practice forbidden at the time but excused by RAAF Bomber Command because of a shortage of skilled air crew.