Qatar has sent around 1,000 ground troops across the border into Yemen to join the Saudi-backed offensive against Houthi rebels, it has been reported.
Military sources told Al Jazeera forces were headed into the country’s Maareb province to join the troops already fighting in the area.
They were reportedly backed by more than 200 armoured vehicles and 30 Apache combat helicopters.
The report comes following an escalation of the conflict after dozens of Gulf Arab soldiers were killed in a missile strike.
Earlier this year, Qatar was described as the "most peaceful country in the Middle East" after it was ranked at 30 out of 162 on the annual Vision of Humanity's peace index – the lowest score in the entire region.
Although this is down eight places on its position last year, it is still high due to Qatar's relatively high levels of internal peace and security, the Doha News reports.
On Sunday, the Saudi coalition carried out an airstrike against key military targets controlled by the Shia rebels and killed at least 24 members of two families, according to AP.
Up to 4,500 people have now been killed in the conflict, including hundreds of children, with the UN issuing desperate appeals for foreign donors after it revealed an estimated 80 per cent of the population needed humanitarian aid in June.
The Independent has contacted Qatar’s Ministry of Foreign Affairs for comment.
Additional reporting by AP and Reuters
In pictures: Yemen water crisis
In pictures: Yemen water crisis
A Yemeni girl sits on plastic jerry cans as she waits get water at a public tap at a slum in the capital Sanaa. In the mountains around Sanaa, farmers are drilling so many unlicensed boreholes to irrigate the thirsty crop for the stimulant plant qat, craved by the capital's residents, that the water table is falling by as much as six metres (20 feet) a year
A Yemeni young boy pushes a wheelbarrow loaded with plastic jerry cans before filling them at a public tap at a slum in the capital Sanaa
A Yemeni child fills a bottle with water as families from the northern city of Amran, 50 kilometres (30 miles) north of Sanaa, take refugee in the capital after fleeing their home as battles between the Yemeni army and Shiite Muslim rebels intensifies
Yemenis gather by a water point to fill their jerry cans in Sanaa as the city suffers a water shortage
A Yemeni woman carries on her head a jerry can after filling it at a public tap at a slum in the capital Sanaa
A Yemeni young boy drinks water at a public tap at a slum in the capital Sanaa. Yemen, ravaged by years of factional strife and widespread poverty, is one of the world's most water-stressed countries with the lack of access to clean water having devastating implications for children
A Yemeni refugee girl fills a container with water in a makeshift kitchen in the grounds of a public school in the port city of Aden, now being used as the living quarters for internally displaced families who had to flee their homes when Al-Qaeda militants swept into southern Abyan province
A Yemeni young boy pushes a wheelbarrow loaded with plastic jerry cans as he arrives to fill them at a public tap at a slum in the capital Sanaa
Yemeni young boys carry plastic jerry cans as they arrive to fill them at a public tap at a slum in the capital Sanaa
A Yemeni young boy carries a can as he arrives to fill it at a public tap at a slum in the capital Sanaa