Saudi Arabia will begin offering visas on Saturday for the first time to non-religious tourists, days after the country was criticised at the UN for its grim human rights record.

The kingdom – which has imprisoned and tortured women’s rights activists, carries out regular public executions, and was responsible for the high-profile murder of the Washington Post columnist Jamal Kashoggi – has said it is opening up to holidaymakers as part of a push to diversify its economy away from oil.

The new visa programme for citizens of 49 countries, including the UK and the US, was announced by Saudi tourism officials, quickly followed by a Twitter campaign exhorting users to @VisitSaudiNow.

As part of the scheme, which promises to deliver a visa in seven minutes, female tourists will be exempted from wearing the all-covering abaya robe, but will be required to dress “modestly”.

The Twitter account, which does not appear to accept comments, has so far posted three times, including promoting an image showing rock climbing and one featuring sheep in what appears to be a snow-covered setting.

Getting tourists to visit the austere kingdom, which forbids alcohol and enforces a strict social code, however, is seen by many as a hard sell.

While Saudi Arabia has a relatively well-established hotel and air transit network, serving the millions of Muslim pilgrims who travel to the country to perform the Hajj and Umrah, its new tourism strategy marks a stark departure.

The announcement comes as the country has been on a diplomatic offensive, both to counter criticism of its human rights record and to bolster its proxy conflict with neighbouring Iran, which has been played out largely in Yemen.

The move also prefigures the anticipated acknowledgement by Saudi Arabia’s crown prince, Mohammed bin Salman, in a PBS documentary next week, that he bears responsibility for the killing of Khashoggi last year by Saudi operatives “because it happened under my watch”.

Kickstarting tourism is one of the centrepieces of Prince Mohammed’s Vision 2030 reform programme to prepare the biggest Arab economy for a post-oil era.

“Opening Saudi Arabia to international tourists is a historic moment for our country,” its tourism chief, Ahmed al-Khateeb, said in a statement. “Visitors will be surprised … by the treasures we have to share – five Unesco world heritage sites, a vibrant local culture and breathtaking natural beauty.”

Tourists at the Al-Wahbah volcanic crater, north-east of Jeddah. Photograph: Amer Hilabi/AFP/Getty Images

He said the kingdom would also ease its strict dress code for foreign women, allowing them to go without the abaya that is mandatory public wear for Saudi women. Foreign women, however, will be required to wear “modest clothing”, he added, without elaborating.

Visas in the desert kingdom, rich in bedouin heritage and archaeological sites, are currently restricted to workers, their dependants and Muslim pilgrims travelling to holy sites in Mecca and Medina.

Among attractions in the kingdom are Nabataean ruins in Madâin Sâlih, once part of the spice route, the palace complex in the Najdi architectural style in Ad-Diriyah, capital of the first Saudi dynasty, and the Red Sea coast.

In a rare move, Saudi Arabia last year began issuing temporary visas to visitors to attend sporting and cultural events in an effort to kickstart tourism.

Prince Mohammed is seeking to change that through a sweeping liberalisation drive that has brought new cinemas, mixed-gender concerts and sporting extravaganzas to Saudi Arabia.

The government, reeling from low oil prices, says it hopes tourism will contribute up to 10% of the gross domestic product by 2030, compared with 3% currently. It says by 2030 it aims to attract up to 100m annual visits by both domestic and foreign tourists.

In 2017, the kingdom announced a multibillion dollar project to turn 50 islands and other pristine sites on the Red Sea into luxury resorts.

Saudi sightseeing

Madâin Sâlih

The ancient archeological site became a Unesco world heritage site in 2008. It is located along an ancient trade route and has a large collection of monumental tombs. With 111 monumental tombs, it is the largest conserved site of the Nabataean civilisation. One remote tomb, known as Qasr al-Farid or the Lonely Castle, is carved into a giant boulder but was never finished.

King Fahd’s Fountain

Standing in the Red Sea between 260 metres and 312 metres high, the fountain is the world’s tallest. It was opened in 1985 and is visible around the city. It does not use freshwater, instead taking the Red Sea’s saltwater.

Jeddah Tower

Construction began in 2013 and has been subject to delays. However, it is expected to be the world’s tallest building on completion in 2020. It will rise at least 1,000 metres, overtaking Dubai’s Burj Khalifa. Previously known as Kingdom Tower, it will be the centre of the Jeddah Economic City development and will contain a Four Seasons Hotel and the world’s highest observatory.

Al Wahbah crater

Once believed to be created by a meteorite, the crater is thought to have appeared due to volcanic activity. Standing at 2km across and 250 metres deep, the bottom is covered with white salt and is home to palm trees and green grass despite being surrounded by desert.

Jubbah rock carvings

The most famous rock art site in Saudi Arabia became a Unesco world heritage site in 2015. Located in the Jabel Umm Sinman range, the carvings cover a wide range of representations including humans, cattle, lions and ostriches. Some of the carvings are possibly 10,000 years old and were created using a range of techniques.