In 2017, Riyadh, along with the United Arab Emirates, Bahrain and Egypt, severed diplomatic and trade ties with Doha over claims that it supported terrorism – a charge that it has long denied.

The Saudi-led bloc had issued a list of 13 demands to the rival emirate, including ending military cooperation with Turkey and limiting trade with Iran.

In January, the blockading countries agreed to end the three-and-a-half-year rift with Qatar, as part of a flurry of diplomatic activity towards the end of former US President Donald Trump’s time in office.

Qatar’s ruler Sheikh Tamim bin Hamad Al Thani travelled to the Saudi city of Al-Ula at the time, for a summit ending the blockade hosted by Crown Prince Mohammed bin Salman.

He did not meet King Salman, but was pictured embracing the Saudi crown prince during the summit, in a clear sign of improving relations.

On Monday, Sheikh Tamim received a letter from the Saudi king that included “an invitation to visit” the kingdom, the emir’s office said in a statement.

No details were provided about whether the invitation had been accepted, or when the proposed visit would take place.

The invite was delivered by the Saudi foreign minister, Prince Faisal bin Farhan, who was in Doha discussing “Gulf unity” with his Qatari counterpart, according to Qatar’s foreign ministry.

The development comes after weeks of steps towards the normalization of relations, including the reopening of the border between the two nations and the resumption of air travel.