A Muslim living in non-Muslim societies should be always keen to perform acts of worship in the right way and at the same time keep intact the fabric of the society he or she is living in.
For instance, a university campus might have limited space and the administration thereby assigned a multifaith prayer room for students following different faiths. When this is the only option for a Western Muslim, there is nothing wrong for him or her to pray in such a room as long as the place is clean tahir. Other important rules to be considered include that he or she prays in a location in the room where there is no statue or image in front of him or her, or that he or she puts a sutrah in front of him or her.
Sheikh `Abdul-Majeed Subh stated,
There is nothing wrong in praying in such a room as long as you do not make the image or statue right in front of you; that is to say, in the direction of the qiblah (Arabic for: direction of the Ka`bah). However, if there is no option but to pray while the images or statues are in front of you, then you can close your eyes and pray. We read in Al-Bukhari’s Sahih a chapter on “Whoever Prays While Fire is in Front of Him.” Fire was being worshipped at that time.
Given the above, if a Muslim offered prayer in such a room and put a sutrah in front of him or her, the prayer is valid.
Moreover, Sheikh Ahmad Kutty adds:
If you can cover them up, it is best to do so; if, however, you are not able to, you can simply make a sutrah and pray.
It is worth remembering that Prophet Muhammad (peace and blessings be upon him) used to pray in the courtyard of Al-Haram (Sacred Mosque) in Makkah while it was populated by idols (before the Hijrah and before the majority of people in Makkah became Muslims). That was in the early days of Islam. So you can do so in exceptional cases if you have no other choice.