PHILADELPHIA (AP) _ A strike that would shut down the city's mass transit appeared inevitable today, as the union president dismissed any hope of a last-minute settlement before a noon deadline.

``We will be on a regional transit strike. It will be shut down at noon,'' said Steve Brookens, president of the Transport Workers Union Local 234.

The Southeastern Pennsylvania Transportation Authority's city system and two suburban transit divisions will be affected, Brookens said. An estimated 200,000 people use the system daily, making a total of 435,000 rides per day.

Philadelphia police were out in force downtown to ensure that traffic moved smoothly.

Some riders were still hoping this morning that they would be able to take mass transit home again this evening. But they were prepared for the worst.

``I guess I'll have to hope a cab is available,'' said Jane Quinn, 71, a former Philadelphia who was back here to visit friends.

``I'll take my time and walk,'' said Joseph Lee, 66. ``Walking could be good to lose a couple of pounds.''

Robert Campbell, 35, a law clerk, said he usually took the bus to work every day. But he drove in today, ``just to be sure.''

When the Transport Workers Union's contract expired March 14, both sides agreed to continue negotiations and avoided a threatened strike. But talks broke down.

Negotiators met with state mediators for about 45 minutes Sunday, but made no progress. Differences remained on health benefits, pensions, work rules, and part-time workers.

``We have done everything we can to stop this freight train from hitting a wall,'' SEPTA chief counsel David L. Cohen said Sunday night. SEPTA urged commuters to carpool or use regional railroads during the work stoppage.

``Unfortunately, we've spent 2 1/2 months trying to negotiate a contract, showing our willingness to compromise, ... and yet SEPTA rejected every compromise proposal we offered them,'' Brookens said.

Kevin Feeley, spokesman for Mayor Edward G. Rendell, said the city was urging union members to accept SEPTA's latest proposal. The strike deadline comes just as the city was trying to impress GOP national convention planners who arrived in town today.

The walkout would involve 5,100 city drivers and mechanics, plus some 320 suburban transit workers whose contracts expired in April.