If a project is held on by the Client for certain period of time, what should the top management do with project team including project manager?

it depends if the client hold the project due to financial or difficulty of execution or manpower problem or the project illegibility or what ever is the client should go by the procedure and inform  the reasons behind holding the project in written and official form and give the higher management enough time to decide on whether to continue or not , it is important to the higher management to understand the reasoning and purpose of such a client in written form , no immediate change on man power should be taken unless all the aspects of the project is clear after all these preparations the higher management should return back to the original contract terms of the project  which  commits both parties if there is a gap in the contract such as risk events are not included in the contract then the only way is to be patient to the client and try flexibility and may be to help find away out if it does not work that way then the percentage of execution  has to be considered to terminate this project and ask for the cost for what ever executed this is legal right but if the client intentions of the client is  to resume contract for some time later again the losses and expenses including man power should be considered and subcontracted again in the new subcontract the terms regarding a situation like this will be added to the subcontract , and enough pledges should be claimed

A couple of people have suggested putting the contract team on unpaid leave or lower salary.  This is dangerous. In general the good people will find other jobs within a matter of weeks, which will have a catastrophic effect on the overall quality of the team.  Those who remain will have significantly reduced morale and commitment to the project. 

In other words, either keep the project team together on full pay, or dissolve it.  

According to period of stopping and the reson of holdind that can prosecution the client, either transfer the staff to another project if the have, or paied half salary to the staff, or keep some (main staff), if the situation is too bad dissolve all and this is really big problem when the project need to start again because most of the skills people will goes to another company.

Either deploy the team in case they have other projects under construction, or give the team unpaid vacation.But the contractor should claim this expences to the client,specially if the hold time is long.

I agree with Mr. Basim and Mr. Mamoun

Thanks for the invitation. In my view, the project manager should consult the customer to know about the reasons behind holding on the project. One can't keep on waiting for a long time hoping to see positive answers from the customer because in this case hope is not your friend and you have to be sure whether you can expect an early approval from the customer to continue working the project or not.

Maybe the reason of hold should be clear, is it legal dispute between client and contractor? 

Or: Financial problems, manpower, difficulties in execution?

I think in all cases this should be communication officially (written) so that maybe a corrective action can be taken, or at least it will be clear who is the responsible party of the hold so that that party will be responsible for any included cost.

Sometimes some or all project manpower and/or equipement (if any) can be reallocation to another project.

Thanks for the invitation.

I agree with Mr. Basim and Mr. Mamoun

I think first we should 100% clear that , why & what the difficulty occurred, then resolve the problem.  

Thanks for invitation -

Agree with Mr.Basim Natour answer .

the management should ask for claim

regarding the stuff i think they should transfer them to other projects if they have, if not vacation for long period until they resuming or find new project