The fire-damaged section of the M1 will open fully again from tomorrow but there could be further closures in the future so permanent repair work can be done, it was announced tonight.
A fire, which is now being treated as arson, broke out under an elevated section of the road just north of London last Friday.
This led to full and part closures of the section between junctions 1 and 4.
It had been expected that a contraflow would have to operate on the section at the start of the Easter period.
But tonight the Highways Agency said the normal three lanes would be open in each direction from tomorrow morning, albeit with a 50mph limit over the fire-affected viaduct.
In the meantime, the part between junctions 4 and 2 will be reduced to one lane in each direction from 9pm tonight to 6am tomorrow to enable the full opening later.
The agency added: "It should be noted that it is likely there will be a need for closures in the future to enable permanent repair work to be undertaken. These will, of course, be planned to minimise disruption as far as possible."
Transport Secretary Philip Hammond said: "I am pleased that work on the M1 has progressed faster than anticipated to allow the safe opening of three normal lanes in each direction by tomorrow. This means there will now be no need for a contraflow system.
"The Highways Agency has been working around the clock to do everything it can to reopen the M1 and this news will be welcomed by motorists planning to get away for the Easter weekend."