大中央鐵路公司為給預定乘坐桑德蘭和倫敦之間的兩趟列車的乘客造成的 "任何不便 "道歉，這兩趟列車早些時候被取消。
Some services have already been affected - with a crew shortage causing to one journey to be cancelled between Sunderland and London earlier.
Grand Central Rail apologised for "any inconvenience" caused to passengers who were booked to travel on two services between Sunderland and London, which were cancelled earlier.
The company said one service was axed due to shortage of crew and the other because "more trains than usual needing repairs at the same time".
Tyne and Wear Metro is largely unaffected by the industrial action but there will be no trains running between Pelaw and South Hylton, as the line is part of the national rail network.
Although replacement bus services are organised for Saturday due to planned engineering works, Nexus (which runs Metro) said it was not possible to provide replacement buses "at short notice on other strike days, so customers should find alternative travel or put off their journeys".
LNER has about 38% of its usual trains scheduled for Tuesday, it warned the remaining services "are likely to be very busy".
Ahead of Tuesday's action, the last LNER service to Newcastle from London is due to leave King's Cross at 21:00, and the last southbound train for London leaves Berwick at 20:19.
Northern has advised passengers "not to travel on any day from Tuesday through to Sunday" because of impact of the action being felt on non-strike days.
At Middlesbrough railway station Denise Longster said the action would disrupt her plans: "I can understand them wanting more money but it's like that for everybody else and the money's not there, we need to get the country back up before asking for a pay rise."
Karl West-Oyston who owns the station cafe, said: "We're doing reduced hours to start with as the footfall coming through the station will be vastly reduced and 50-60% of our trade comes from the footfall."
The industrial action is being taken by members of the RMT union, whose members are unhappy at pay, pensions and proposed job losses.