KUALA LUMPUR, Nov 30 ― Tun Dr Mahathir Mohamad today welcomed the authorities to investigate his finances, saying his books are clean amid continuing allegations surrounding supposed “rewards” he had after he stepped down as prime minister.

Among the latest allegations was the acquisition of land in Langkawi.

Detractors of Dr Mahathir, including another former prime minister Datuk Seri Najib Razak, claimed the land was given to him free, which the Langkawi MP rejected.

“Land leasing comes with payments and is not a gift like some people are claiming it to be. I did not get it for free, not even a discount.

“However there are individuals, frothing at the mouth, accusing me of abusing my powers as a former prime minister,” Dr Mahathir wrote on his personal blog.

“I bought two plots of land in Langkawi after I retired and was not given anything as a gift for free from the federal or state government. In fact the cost of rent was increased so many times that in the end I returned the land to the Langkawi Development Authority (LADA).”

Dr Mahahtir said he used the land for cultivating vegetables and rearing cattle; adding that some of them were successful and the others not.

He said instead that he, his wife and his children had been harassed by the authorities and questioned by the Inland Revenue Board.

He challenged the authorities to investigate him if there was any wrongdoing.

“If it’s true I did something wrong, then charge me. I have paid all my taxes and do not need to ask for permission for my passport to travel.

“I have nothing to hide,” he added.

Najib had come under scrutiny recently after his application to the government seeking a plot of land and house in Kuala Lumpur as entitled by former prime ministers was made public. The property was reported to be worth over RM100 million.

The news, reported during the Melaka state election campaign, drew attention as Najib was an active campaigner for the Barisan Nasional who has been convicted and sentenced to jail for multiple counts of money laundering and corruption in the misappropriation of SRC International Sdn Bhd.

The Pekan MP is also on trial on multiple other similar charges surrounding sovereign fund 1MDB.

Najib later retracted his request but poured scorn on Dr Mahathir, accusing the 96-year-old of similar practices when he was prime minister.

Najib also questioned the Opposition MP's use of the Perdana Leadership Foundation’s office in Putrajaya.

Dr Mahathir has said the allegations were a diversionary tactic to distract people from the many charges Najib is facing in Court and that the Putrajaya land was also bought and not given for free like Najib claims.