Thaksin Shinawatra is now carrying six passports issued by foreign countries, Puea Thai MP chief Chalerm Yubamrung says.
Mr Chalerm recently visited the former prime minister in Dubai but was unable to give details of which countries had issued Thaksin with the passports.
Nicaragua reportedly issued Thaksin with a diplomatic passport when he was selected to promote the country's trade and investment.
Thaksin may also have obtained a passport from Montenegro. Mr Chalerm yesterday confirmed Thaksin planned to buy an island off the Montenegrin coast in the Adriatic Sea.
Mr Chalerm said his trip to Dubai in the United Arab Emirates (UAE) focused on business opportunities. No political issues were raised with Thaksin, he said.
Thaksin often travelled from place to place in a helicopter he bought from the owner of the luxury Harrods store in London, Mr Chalerm said.
The former prime minister is living in exile after fleeing the country while awaiting trial on charges of abuse of power while in office over the Ratchadaphisek land deal.
Thaksin is reportedly based in Dubai where he has major business interests.
The government has tried to restrict his movements by cancelling his Thai passport.
Mr Chalerm insisted he had no idea if Jakrapob Penkair, a co-leader of the anti-government United Front for Democracy against Dictatorship (UDD), was staying with Thaksin.
Mr Jakrapob fled Thailand after the Songkran riots to escape charges that he and his fellow UDD leaders had instigated violence.
Meanwhile, Pol Maj Gen Visanu Prasartthong-osod, chief of the Royal Thai Police Office's foreign affairs division, said the latest checks had found Thaksin had entered the UAE and there was no evidence he had left again. If he had left, he might have done so using a different name.
The foreign affairs division has asked Interpol's UAE branch to check if Thaksin has travelled under another name.Pol Maj Gen Visanu believed Thaksin was still in the UAE, using it as a base to contact his supporters in Thailand.
He said his division had yet to translate copies of Thaksin's interviews with foreign media considered to be defamatory to the monarchy.