Despite the fact that Saudi Arabia, the first independent entity in the Gulf region, was the first among the GCC member-states to establish full diplomatic relations with Thailand, an event which took place in 1957, bilateral relations between the two kingdoms have become tense and strained.
This can be seen in Riyadh's decisions to ban the recruitment of Thai workers, to stop its citizens from travelling to Thailand, to end all its national carrier's flights heading to Bangkok, and to force its businessmen to replace their Thai employees with others, something that caused a sharp drop in the number of Thais in the Kingdom from 200,000 in 1989 to only 10,000 at the present.
Such unfriendly decisions, which followed years of warm and amicable relations, particularly in the 1970s, when Saudi Arabia opened its doors wide to hundreds of thousands of Thai workers and hundreds of Thai engineering and consulting companies, reflect - according to one source - Riyadh's uneasiness about the way Bangkok had handled the assassination case of five of its diplomats in 1989 and 1990 and the mysterious disappearance of one of its businessmen in 1989.
In other words, Riyadh accused Thai police of cooperation with or at least providing protection to the assassins - believed to be members of the Iranian intelligence or Lebanese Hezbollah.
Other sources believe the setback in Riyadh-Bangkok ties is a result of what is widely known in Thai press as "the Blue Diamond" case.
The Saudis are said to be very angry, not only because of Thailand's failure to adequately investigate and explain the murder of five Saudi citizens in Bangkok - or because of its failure to take action against high-ranking generals, believed to have connections with Kriangkrai Techamong, a Thai national accused of stealing a huge amount of jewellery from the palace of his employer, a prominent Saudi Prince, in the 1980s - but also because Thai police had tried to cheat them by returning to Saudi Arabia jewellery that turned out to be fake, including the so-called Blue Diamond.
The Saudis who downgraded their diplomatic presence in Bangkok to the charge d'affaires level as a sign of protest, seemed to be determined to go ahead with the case until the perpetrators were put behind bars or at least until their names and their lives were ruined.
They also seemed to be in a hurry as, according to Thai law, these cases will expire in less than two years. Nothing proves this better than Bangkok-based Saudi diplomats' requests to have meetings to discuss the case with Thai officials every time a new government is formed in Bangkok.
While this is the scene as far as Riyadh-Bangkok ties were concerned, ties between Bangkok and other GCC member-states have not only continued growing, but have also been characterised by warmth, intimacy and mutual confidence.
The best example, in this context, is the relationship between Manama and Bangkok, whose officials exchange visits regularly at the highest level.
The two countries' bilateral cooperation has, in fact, expanded to fields other the traditional ones, such as human resources, high education, health, oil and gas.
Recently, the two sides signed a framework agreement aimed at creating favourable conditions for greater economic cooperation, eliminating barriers to trade to zero per cent by 2010. The Thais correctly view Bahrain as the best place in the region to be the gateway for their products to other Gulf states.
Kuwait was the second Gulf state, after Saudi Arabia, to establish formal diplomatic relations with Thailand. This took place on June 14, 1963. Since then, the two countries have enjoyed a very good relationship in such aspects as trade, finance, industry, education, tourism and transportation.
Kuwait was the first Gulf country to sign an open skies agreement with Thailand, something that allowed national carriers of the two sides to operate flights with no restrictions on plane models, number of seats, number of flights, or airports of landing.
Such cooperation and cordial ties were reinforced by the official visit to Bangkok in June 2003 by the Emir of Kuwait Shaikh Sabah Al Ahmad Al Jaber Al Sabah, during which the two sides signed an important agreement on joint investment and joint venture.
The two most important fields of cooperation between Thailand and the UAE, which established formal diplomatic relations on December 12, 1975 are commerce and tourism.
Emirati citizens are said to view Thailand as a favourite destination for tourism, recreation and medical treatment. As a result, the number of Emirati tourists heading to Thailand are increasing at an average of 60,000 every year, according to one source.
One of the early fields of cooperation between the two parties has been labour. In 2006, there were some 3,500 Thai workers in Dubai alone. This figure jumped to 6,500 in 2007. On November 1, 2007, the two countries signed a memorandum of understanding aimed at protecting the rights of Thai workers living and working in UAE.
Qatar and Thailand established formal diplomatic relations on August 7, 1980. And since then the Thais eagerly worked to expand and cement their export-import ties with the Qataris, something that can be supported by Bangkok's recent decision to establish a commercial office and permanent exhibition in Doha.
In 2001, Thailand imported from Qatar oil, chemicals and fertilisers worth $253 million, while it exported to Qatar commodities and services worth only $19.6 million.
It is important to mention here that the years 2002 and 2008 can be considered as special years in Doha-Bangkok relations, In 2002, the Qataris showed unprecedented interest in investing in Thailand's sectors of finance, minerals and oil.
And in 2008, Qatar opened a new market for its liquefied natural gas industry by sealing a long-term supply deal with Thailand.
Finally come Muscat-Bangkok ties which are characterised by mutual cooperation to explore and produce oil and gas in third countries that could be in Asia or the Middle East.
This is regarded as one of the fruits of an agreement signed in December 2007 between the Omani Ministry of Oil and Gas and PTT, the first Thai oil company to get involved in the Middle East.
Muscat-Bangkok bilateral ties have been additionally reinforced by a decision by Oman Air, Oman's national carrier, in January 2006 to run a non-stop flight to Bangkok, in a bid to use Thailand as its Southeast Asian regional hub.
Dr Abdullah Al Madani is an academic and lecturer on Asian affairs.