4. The framework for co-operation with third countries in order to determine or confirm the child’s nationality 14. Co-operation between states is key, as underlined in the Convention on Jurisdiction, Applicable Law, Recognition, Enforcement and Co-operation in respect of Parental Responsibility and Measures for the Protection of Children of the Hague Conference on Private International Law.17 This is also recognised in Article 23 of the European Convention on Nationality (ETS No. 166) concerning information on relevant legislation and developments. Co-operation should notably address case-specific issues, in particular on the possible acquisition or non-acquisition of nationality. Lack of information may lead to situations of statelessness for the child concerned. 15. Co-operation is essential if a stateless child can access to the nationality of a parent’s state. The state of birth or residence of such a stateless child should provide them with any necessary assistance to exercise that right. 16. However, a child’s parent may face critical impediment in the exercise of the right to acquire a particular foreign nationality. If (the parents of ) a child cannot, for compelling reasons, be expected to acquire that nationality, rules to avoid statelessness of the country of birth should apply, for instance if the parents have left the state of their nationality to become refugees. 17. In the determination of whether a child would otherwise be stateless, decision-makers must adopt an appropriate standard of proof, and all relevant evidence must be assessed, including statements from the parents or experts and any information on how national legislation is applied in practice. In this regard, co-operation between states is essential to avoid statelessness. The competent authority should be able to directly contact consular representatives of other states to confirm the foreign nationality of a child, if necessary, except in cases where security or refugee law-related considerations would prohibit such contact. 17. HCCH Convention of 19 October 1996 on Jurisdiction, Applicable Law, Recognition, Enforcement and Co-operation in Respect of Parental Responsibility and Measures for the Protection of Children. Page 10 ►Access to nationality for stateless children