A Cape High Court judge late on Tuesday night ordered that the new Immigration Act, the bulk of which was supposed to come into force at midnight, should be put on hold.

The ruling by judge Deon van Zyl followed a day of drama in which he and Cape Judge President John Hlophe earlier declared that the regulations which accompany the act were invalid and unconstitutional.

Ruling in favour of an urgent application by immigration lawyers Eisenberg and Associates, they found Home Affairs Minister Mangosuthu Buthelezi had not followed essential notice and comment procedures before gazetting the regulations.

The ruling created what Buthelezi's ministry described as a "legal and factual impossibility", in which officials would have to apply the regulations of the old Aliens Control Act to the new legislation.

Buthelezi's legal team then lodged notice of his intention to appeal the ruling, which would have had the effect of automatically suspending the judges' earlier ruling on the new regulations.

However, late on Tuesday night, as Eisenberg's lawyers threatened to seek an order effectively suspending the automatic suspension, Judge Van Zyl issued another order, this time that the old act and its regulations remain in force until 6pm on March 17.

He said this was an interim arrangement intended to give both parties the opportunity to approach the court for any further relief they required and "sort things out" - Sapa.