LHASA - Heavy snow has blocked the only road that connects the remote Tibetan county of Medog with the outside world, according to local authorities.

Snow has covered the mouth of the Galung La tunnel on the highway linking Zhamog township in Tibet with Medog and may trigger an avalanche, said Li Wei, director of the county's transport bureau on Thursday.

Traffic into and out of Medog is suspended until April 10, Li said, adding that the date might be revised in compliance with weather conditions.

The county government is prepared to sustain its people through the isolation with sufficient food and commodities, said Tashi, the county head.

With about 10,000 residents, sparsely populated Medog is the last of China's 2,100 counties to only be accessible via a single highway.

The construction of the 117-km Zhamog-Medog highway started in April 2009 and is expected to be completed by the end of this year, Tashi said.

However, the highway has become partly operational as the first phase of the project, the 3.3-km Galung La tunnel was finished in December 2010.

Situated at Tibet's border with India and nestled among snow-capped mountains, Medog only has mountain paths connecting its villages and towns.