The Thai government is planning to track foreigners’ phones by issuing special Sim cards to tourists visiting the country.

Its National Broadcasting and Telecommunications Commission (NBTC) has insisted the move is not a breach of privacy and will help authorities catch criminals and anyone overstaying their visa.

“It is not to limit tourists' rights. Instead it is to locate them which will help if there are some tourists who overstay or run away,” secretary-general Takorn Tantasith said.

Gemalto CEO Olivier Piou shows a cell phone sim card before a press conference on February 25, 2015 in Paris. (AFP/Getty Images)

He later clarified that the NBTC has no authority to check people’s locations, adding: “But if tourists commit wrong, or there is a court warrant, we will then forward the warrant to a mobile phone operator and seek co-operation.”

The Sim cards would come with tracking enabled that cannot be switched off by users, the BBC reported.

It was unclear how the policy would be implemented and Mr Tantasith said discussions would be held with police and tourist agencies.

The rule would not apply to expatriates, who are already registered with authorities and must show their passports before buying Sim cards or starting new mobile phone contracts.

Thailand’s military government is backing the proposals, which come as 32 million visitors are expected to arrive in the country to see its famed temples and tropical beaches this year.

“It will be helpful if any foreigner comes and commit crimes, because in the past they have been able to flee or it can be difficult to find them,” said Pongsathorn Chansri, from the Ministry of Social Development and Human Security.

The junta, named the National Council for Peace and Order (NCPO), has ruled Thailand since seizing power in a 2014 coup, when the military ousted Yingluck Shinawatra's government, imposed a state of emergency and martial law.

A disputed referendum on Sunday saw the country back a new military constitution by 61 per cent to 39 per cent.

Thais approve new constitution in referendum

Politicians from both sides of the divide and rights groups opposed draft charter, which includes clauses for a fully appointed Senate complete with seats reserved for chiefs of the armed forces.

Other provisions would make it difficult for a single party to win a majority in the 500-member lower house, driving weak coalitions and allowing the Senate to play a critical role in parliament.

Thai Prime Minister and former army commander, Prayuth Chan-ocha, has called for Thailand to accept the outcome amid fears the laws will stifle democracy.

Human Rights Watch said the constitution facilitated “a deepening dictatorship”.

The group’s Asia director, Brad Adams, said opponents to the move had been repressed and that the rights to freedom of expression, association and assembly were absent from the referendum campaign.

“The Thai junta’s campaign of repression against opponents of the proposed constitution ensured that the referendum wouldn’t be fair,” he added.

Thailand protests: Thai army declares martial law Show all 25 1 /25 Thailand protests: Thai army declares martial law Thailand protests: Thai army declares martial law Thailand A Thai soldier stands in front of a portrait of Thai King Bhumibol Adulyadej as he patrols near government buildings in Bangkok Thailand protests: Thai army declares martial law Thailand A pro-government protester points at a soldier during a cleanup at a pro-government demonstration site on the outskirts of Bangkok Thailand protests: Thai army declares martial law Thailand Thai soldiers patrol near government buildings in Bangkok Thailand protests: Thai army declares martial law Thailand A soldier walks past barefoot Buddhist monks begging for alms outside a temple near Government House in Bangkok Thailand protests: Thai army declares martial law Thailand Thai police and army soldiers stand guard outside a military compound before former Prime Minister Yingluck Shinawatra arrives to report to Thailand's ruling military in Bangkok Thailand protests: Thai army declares martial law Thailand Thai soldiers stand guard at a roadblock outside the Defence Ministry building (background) after Thailand's army chief announced that the armed forces were seizing power in Bangkok Thailand protests: Thai army declares martial law Thailand Thai soldiers patrol after army chief General Prayut Chan-O-Cha met with anti-government and pro-government leaders at the Army Club in Bangkok Thailand protests: Thai army declares martial law Thailand Thai police and military display a haul of weapons seized during recent raids since the imposition of martial law, at a press conference at the Army Club in Bangkok Thailand protests: Thai army declares martial law Thailand Thai soldiers stand next to the portrait of King Bhumibol Adulyadej after the declaration of martial law at the Army Club in Bangkok. Thai Army Chief Prayuth Chan-ocha, declared martial law giving the military full control to prevent further protest-related violence in the country Thailand protests: Thai army declares martial law Thailand Anti-government protest leader Suthep Thaugsuban (R) gives a traditional greeting to a soldier before leaving Government House in Bangkok. Thailand's army chief said rival political groups should talk to each other and that the martial law imposed would last until peace and order had been restored Thailand protests: Thai army declares martial law Thailand A Thai soldier stands outside the Government Public Relations Department in Bangkok Getty Images Thailand protests: Thai army declares martial law Thailand Thai soldiers man a checkpoint near pro-government "red shirt" supporters encampment in suburbs of Bangkok Thailand protests: Thai army declares martial law Thailand (L-R) Thai Police Chief Adul Saengsingkaew, Navy Chief Adm Narong Pipattanasai, Army Chief General Prayuth Chan-ocha and Air Chief Marshall Prachin Chantong during a meeting at the Army Club in Bangkok. Thailand has been wracked by six months of non-stop protests seeking to topple the government. At least 25 people have died in political-related violence and more than 700 injured Thailand protests: Thai army declares martial law Thailand Motorists on their way as Thai soldiers take to the streets with a heavy machine gun on a Humvee military vehicle at a main road outside the Royal Thai Police Sports Club in Bangkok Thailand protests: Thai army declares martial law Thailand Outside police headquarters in Bangkok Getty Images Thailand protests: Thai army declares martial law Thailand An anti-government protester waves a Thai national flag during a rally outside the Government House in Bangkok. Thailand's Senate said it was ready to choose an interim prime minister to end a political deadlock but stopped short of throwing out a beleaguered caretaker government and risking a violent backlash by its supporters Thailand protests: Thai army declares martial law Thailand Thai anti-government protesters shout slogans during a rally in front of the Parliament as senators debate to find and end to the country's political conflict in Bangkok. Thousands of anti-government protesters rallied the area surrounding parliament and Government House to pressure the Senate to appoint an interim government to institute political reforms before new elections while key Thai institutions are resisting the opposition's demands Thailand protests: Thai army declares martial law Thailand Thai anti-government protesters gather in front of the Parliament in Bangkok Thailand protests: Thai army declares martial law Thailand Thai riot policemen stand guard during an anti-government protest rally at the Air Force auditorium in Bangkok. Thailand's Election Commission called for the postponement of key parliamentary polls due to be held on 20 July 2014 because of political unrest shaking the kingdom Thailand protests: Thai army declares martial law Thailand Anti-government protesters leave an air force base after breaking into its grounds in Bangkok. Protesters seeking to oust Thailand's government broke into the grounds of an air force compound where the acting prime minister was meeting the Election Commission to fix a date for new polls, forcing him to flee Thailand protests: Thai army declares martial law Thailand Thai Air Force military (L) face anti-government protesters after they broke into the Royal Thai Air Force base in Bangkok. Hundreds of anti-government protesters broke into the meeting between the election commission and the caretaker government as they discussed for the planned next elections on 15 May 2014, after the results of the 02 February general elections were annulled. According to media reports, Thailand's Election Commission said that the 20 July polling is no longer possible due to political turmoil Thailand protests: Thai army declares martial law Thailand Thai anti-government protesters leader Suthep Thaugsuban (C-L) cheers his followers during a street rally march toward Government House and Parliament in Bangkok Thailand protests: Thai army declares martial law Thailand An anti-government protester (C) gives instructions to a fellow protester on how to wave a huge Thai flag from atop a barricade near the Government House in Bangkok. Thailand's beleaguered government warned people to stay away from anti-government protests, saying it had to step up security as the two sides in a lengthy political crisis squared off over who is running the country Thailand protests: Thai army declares martial law Thailand An anti-government protester looks at a damaged telephone booth after a grenade attack at a protest site outside Government House in Bangkok. Supporters of Thailand's embattled government warned the country's judiciary and Senate against any attempt to install an unelected prime minister, saying it would be a disaster for the nation that could spark civil war Thailand protests: Thai army declares martial law Thailand Anti-government protesters making a fist and waving a giant Thai flag, the symbol of the protest, on top of a truck as they rally outside Thai Parliament in a call for the final battle in Bangkok. Protesters marched on many key sites in Bangkok, police fired tear gas and some protesters have been injured. Protest leaders say they are hoping to strike the final blow at the weakened government and usher in a people's council to reform the government

“Instead of the long-promised return to democratic civilian rule, the new constitution facilitates unaccountable military power and a deepening dictatorship.

“It will entrench the abusive military rule that Thailand has endured since the May 2014 coup.”

For more than a decade, Thailand has been divided between populist political forces led by former Prime Minister Thaksin Shinawatra, who was toppled in a 2006 coup, and the royalist and military establishment, which accuses him of corruption and nepotism that he denies.

Mr Prayuth, seeking to allay concern he might delay plans for a vote, said a general election would be held in 2017.

The US and European Union have urged a quick return to democracy, calling on authorities to lift restrictions on freedom of expression.