The tunnel is not classified as a trunk road

The work is necessary to bring the link into line with European fire safety regulations.

The local authority is asking the Scottish Executive to come up with the cash to fund the project.

But ministers insist that the responsibility for the route rests with the city council.

Network review

The Scottish Executive is responsible for trunk roads like the Kingston Bridge and the Erskine Bridge, which both also cross the Clyde.

However, the Clyde Tunnel - which is used by about 65,000 vehicles each day - is not classed as a trunk road.

Transport Minister Nicol Stephen said: "I am sure that the case will be argued for the Clyde Tunnel to be included when we have another trunk road network review.

About 65,000 vehicles use the tunnel each day

"But as recently as the mid-1990s we had such a review and it was agreed that the responsibility for the tunnel would remain with the council."

However, that stance has angered the local authority.

It said this was the first time that it had approached the Scottish Executive seeking money.

Councillor Willie O'Rourke said: "Glasgow has maintained the tunnel since its inception out of its own budget.