Beijing's move has immediate economic consequences: the summer is the best time for travel to the autonomous region, and culminates with some Buddhist festivals in August.
The Chinese Foreign Ministry spokesman, questioned by journalists about the meaning of the ban, said he did not know why. The managers of travel agencies say that there must be some "political motivation" behind the move and imagine it is a "punishment" for the Tibetan demonstrations last May, on the 60th anniversary of the communist government in the region.
But the ban was issued in early June, when the anniversary had already passed. The most likely hypothesis is that Beijing wants to avoid facing July 1, when the whole country will celebrate 90 years since the founding of the Chinese Communist Party.
China fears riots similar to those in 2008, just months before the Olympics, which killed 22 Chinese people (according to Beijing). According to the local Tibetans over 150 people died.
In recent weeks, there tension has been high in Tibetan Sichuan at Kirti, where a monk set himself on fire to protest against the Chinese dictatorship. The police then surrounded his monastery, and forced the monks to political indoctrination sessions.
According Penpa Tsering, president of the Tibetan parliament in exile, Beijing's decision "shows that while China celebrates 60 years of the 'liberation' of Tibet, it wants to avoid the reality of the situation being seen by foreigners. If all that the Chinese claim is true, why this fear? They have no confidence in the domestic situation and fear that Tibet is seen by independent sources of the international community. "