My answer is based on the children residing in the UK if that is not the case then you may need help form a different lawyer. The police may be reluctant to provide the information especially if they cannot verify your identity, for obvious reasons. I would look at providing them with the proof they require as soon as possible. However, by process the police are unlikely to telly what accusations have been made before they have had the opportunity to investigate this. You ex. partner will be withholding contact from you on the basis of safeguarding. What you will require to do is get the matter to court and obtain an order providing you with contact. Prior to this being granted, the court will likely instruct cafcass, to do what is called a section 7 report. This is when they will look into all matters and accusations etc. and also speak to the child/children and listen to what they have to say. Once this report has be submitted to the court, the judge will consider all other evidence and what you and the other parent have to say. Based on this information, the judge will make a decision one what is going to happen. If contact is ordered between you and the children or they have to reside with you moving forward then this will be legally enforceable. These can be quite complex issues and if possible I would advise instructing a solicitor to represent you.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
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