The engineers building the new road bridge over the Forth say its revised opening date of May is "realistic but not guaranteed".

The £1.35bn Queensferry Crossing had been due to start taking traffic last month until bad weather delayed construction.

With the revised opening date now four months away, only one last section of the bridge's deck has still to be lifted into place.

The Forth Crossing Bridge Constructors hope to complete that part of the five year project within the next ten days, forming a new continuous link between Fife and the Lothians.

The final phase of the work will include four concrete pours, the installation of the last 20 cables, laying and waterproofing the 100,000 square metre roadway, and fixing into place 35km of wind shielding.

Low temperatures and prolonged rain would hamper some of the work but the engineers in charge say the planned timescale is "credible" unless this winter weather is unusually severe.