The King of Nepal, who seized power yesterday after sacking the country's interim government, has announced a new government led by himself and a 10-member cabinet packed with his own supporters.

He made the announcement as opposition politicians said dozens of their members had been detained yesterday and today, and many more were in hiding as extra riot police patrolled the streets of the capital, Kathmandu.

King Gyanendra has declared emergency rule and virtually isolated his nation from the world by cutting phone lines and internet connections, prompting criticism from the UN, Britain, the US, India and human rights groups.

The king denied he had perpetrated a coup, although soldiers surrounded the houses of former prime minister Sher Bahadur Deuba and other former government leaders. Shovakar Parajuli, of the centrist Nepali Congress party, said at least 50 of the group's top leaders had been arrested.

King Gyanendra justified seizing power for the second time in three years because the government had failed to hold elections or secure peace with the country's Maoist rebels, who government forces have been fighting for almost 10 years. The king pledged to restore democracy and secure peace within three years.

The Maoists, who control much of rural Nepal, broke off peace talks in August 2003. The rebels had balked at invitations from the government of Mr Deuba to renew the talks, insisting that real authority was in the hands of the king. More than 11,000 people have been killed in the fighting, which started in 1996.

The new home minister, Dan Bahadur Shahi, said the government would soon approach the Maoist rebels - who want the monarchy replaced with a people's assembly and socialist state - to renew talks. "The king has the chief executive authority now, so it will be easier for the rebels to come for peace talks," Mr Shahi said on state radio. "It is what they have been wanting."

But the UN secretary general, Kofi Annan, called the king's actions "a serious setback" that would not bring lasting peace or stability to Nepal, and urged him to take immediate steps to restore "democratic freedoms and institutions".

Three human rights groups - Amnesty International, Human Rights Watch and the International Commission of Jurists - expressed concern that the monarch's moves put "the Nepalese people at even greater risk of gross human rights abuses".

The British government made it clear that the £41m it gives in aid to Nepal had been put at risk.

King Gyanendra has suspended several provisions of the constitution, including freedom of the press, speech and expression, peaceful assembly, the right to privacy, and the right against preventive detention.

The small Himalayan nation, which is wedged between Indian and China, remains largely isolated today. Soldiers were deployed at some private internet service providers to make sure they remained disconnected. The airport was open, but only limited flights were going into Kathmandu.

Despite political turmoil, and extra police on the streets, most shops in Kathmandu were open and traffic was still heavy enough to clog the city's maze-like streets.

However, the situation could grow more complex tomorrow when a nationwide three-day strike called by the rebels could shut down much of the country. The strike was announced before the current political crisis began.

Analysts said the king's move was an attempt to return to the era of absolute power enjoyed by the royals before King Birendra, Gyanendra's elder brother, introduced democracy in 1990.

Nepal has been in turmoil since King Gyanendra, 55, assumed the crown in 2001 after Birendra Gyanendra was gunned down in a palace massacre by Birendra's son, the crown prince, who was high on drink and drugs and also killed himself. Ten members of the royal family were killed in the attack.

Riots shook Kathmandu after the killings. Fighting then intensified between government forces and the rebels, who say they are inspired by the late Chinese revolutionary leader, Mao Zedon.