An Egyptian human rights group has said it will transfer its regional and international activities abroad because the state has "declared war" on civil society groups.

The Cairo Institute for Human Rights Studies (CIHRS) said on Tuesday that it feared "constant threats" against non-governmental organisations and a clampdown on all "critical voices" would hinder its work.

The group citied a government ultimatum to thousands of groups, which expired on 10 November, to register under a law from the era of Hosni Mubarak as one of the main motives behind the move.

The centre said it feared it would also be obliged to relocate its local activities "if the hostile climate against independent human rights group continues."

Regional activities will be moved to Tunisia, where the group is legally registered, the centre said.

Some regional activities were relocated to other Arab countries amid restrictions that either impede or bar foreign rights campaigners and academics from entering the country, a statement by the centre said.

Last month, the government gave a deadline for groups doing NGO-type work and registered as civil companies or law firms to correct their status by registering under the Mubarak-era statute.

NGOs also fear a new draft law regulating their activities will further strengthen the state’s grip on them and severely restrict their operations.

Social Solidarity Minister Ghada Wali said she was "astonished" by the group's move, in comments carried by state news agency MENA.

The minister said she had previously accepted the group's call for a dialogue, stressing that the government has taken no legal action against the group or cracked down on it.

Wali said the institute had not asked the government for a correction of its status.

Some rights groups have already shut their offices in Egypt, including a democracy watchdog founded by former US president Jimmy Carter.

The Carter Centre said it had closed its Cairo office in October because "the current environment in Egypt is not conducive to genuine democratic and civic participation."