Deputy Opposition leader Tanya Plibersek says Kevin Rudd could play a part in easing diplomatic tensions with Indonesia.

But she is not sure whether the former prime minister, who has now left politics, would want to help.

“Any senior Australian like Kevin Rudd, who as former prime minister and former foreign minister, if they’ve got personal relationships with senior Indonesians, it does no harm to be talking in that personal context to them,” she told ABC television.

Mr Rudd was prime minister in 2009 when it is alleged Australian intelligence monitored the phone calls of Indonesian President Susilo Bambang Yudhoyono, his wife and some of his closest confidants. In the escalating diplomatic row, Indonesia has stopped joint defence activities and threatened further retaliation.

Ms Plibersek says it all depends now on the letter from Prime Minister Tony Abbott to President Yudhoyono, who is demanding a formal apology and a full explanation of the phone-tapping charges.

She says she does not know what’s in the letter. “The proof will obviously be in the pudding. If co-operation is restored to its normal settings, then we will know that the letter has been successful,” she said.

Mr Abbott had not helped the situation with his addresses to parliament, Ms Plibersek said. Neither had the coalition’s election policies of turning back asylum seeker boats and its failure to consult Indonesia. “I am sure that we will get the relationship back on track but we need to do it quickly,” she said.