Earlier this week, Burmese authorities closed a key border crossing on the Moei river in Mae Sot in Thailand’s Tak province.

The move followed Thailand’s temporary closure of the border crossing in Kanchanaburi province after the kidnapping of two Thai border police officers in Sangkhlaburi district by members of the Democratic Karen Buddhist Army-a splinter group of the Karen National Union with close ties to Burma’s ruling junta.

The closing of the Mae Sot-Myawaddy border crossing is believed to have been in retaliation for the Sangkhlaburi closure.

Burma knows well the value of the Mae Sot-Myawaddy crossing, as trade through this portal generates about 40 million baht each day. However, they might also believe they have the upper hand in dealing with Thailand, and so can endure the lost trade revenue temporarily.

And Burma has plenty of other avenues for their brisk trade in teak, seafood, livestock and other goods-not to mention revenue from natural gas and other natural resources.

Border closings are a common element in the hot-and-cold relationship between the two countries, particularly when relations sour or on occasions when border tensions produce occasional armed conflict.

Thailand’s provincial governor in Mae Hong Son on Friday took the next step in the current tit-for-tat diplomacy by closing that province’s border checkpoint. This move comes on the heels of a grenade attack allegedly by Burmese border troops that killed one Thai ranger last week.

Officials from both countries continue to meet over the issue, but with little success so far.

Relations between Burma and Thailand have been uneasy since Surayud Chulanont became prime minister in October last year. His appointment by Thailand’s military-led interim government, installed following a bloodless coup that unseated the government of Thaksin Shinawatra, has done little to smooth longstanding tensions among the Burmese, particularly because he is widely seen as being sympathetic to Burmese ethnic groups along the border.

As the former army chief in the early 2000s, Surayud ordered several border closings to stem the flow of drugs into Thailand, believed to be coming from the Wa region of Burma. That period also saw several border clashes with Burmese soldiers, and several months passed before relations normalized.

Surayud has maintained only minimal contact with Burma’s ruling generals, with the exception of a brief visit as part of an Asean tour after his appointment as premier late last year.

Sources along the border suggest that the junta and its allies within Karen State want to pressure Thailand for allowing members and leaders of the Karen National Union to live on Thai soil. Others believe that Burma is merely flexing its muscles while Thai security forces are busy with an increasingly blood insurgency in the southern provinces.

But some Thai officials seem willing to appease the Burmese regime and restore some balance to deteriorating relations.

In early March, Thai soldiers stopped a small group of Burmese monks from finishing a “freedom march” from Bangkok to Mae Sot. The peaceful march was conceived to draw attention to international and regional demands for the release of all political prisoners in Burma.

Thai police in Mae Sot also broke up a hunger strike led by Burmese demonstrating in support of the monks’ freedom march and increased security measures near the homes of Burmese opposition leaders in Mae Sot.

A group of Asean Inter-Parliamentary Myanmar Caucus members who visited Mae Sot last week were also told by local authorities not to visit dissidents and human rights offices in the city, though they were allowed to call on the medical clinic run by Dr Cynthia.

These developments have led some analysts in Mae Sot to suggest that Thai authorities are unwilling to allow sensitive Burma-related political activities on Thai soil that could prove embarrassing to Burma.

The border closures may be business as usual in the frequently turbulent relations between Thailand and Burma; or, they may be an effort by Naypyidaw to create a more complex diplomatic row in order to pursue some political advantage.

But if relations don’t improve in the coming weeks, Surayud may be compelled to take a break from politicking in Bangkok and the troubles in the South, because the Burmese are knocking on his door.