The US embassy in Nepal's capital Kathmandu may close to the public for security reasons, the State Department said in an advisory to citizens.

The department's fresh "public announcement" alerted citizens to the "possibility of civil unrest in and around Kathmandu and other urban centers in Nepal in reaction" to the king's actions on Tuesday which had led to strong international condemnation.

"US citizens in Nepal are urged to maintain a low profile, to avoid all road travel in and around Kathmandu Valley, and to exercise extra caution until the situation stabilises," the advisory said.

It said however that there was no indication of any direct threat to private or official American citizens in the Himalayan kingdom.

Although Kathmandu's international airport has reopened, the advisory said Nepali authorities might impose curfews with little if any notice. It added that land and mobile telecommunications may not work at times.

"From time to time, the US embassy may close to the public for security reasons," it said.

Meanwhile, the European Union on Wednesday joined international condemnation of Nepalese King Gyanendra's dismissal of his government and swearing in of a new cabinet dominated by royalists.

The EU's Luxembourg presidency called for a "speedy" return to multi-party democracy.

"The EU is deeply concerned about the dissolution of the multiparty government in Nepal and the decision by the king to assume executive powers," it said in a statement in Brussels.