No one can block open common area meant for all. Report the matter to police, RWA, municipal corporation of area, registrar of societies and also suit for permanent and mandatory injunction. Consult a competent lawyer. 

issue legal notice to neighbour to remove the blockage of common space

2) if he refuses file suit seek court orders to direct neighbour to remove blockage of common area as it has resulted in pigeon infestation 

Space between balcony and common shaft is common area as defined under RERA. Even if the apartment is not under registered RERA such are is within the purview of “common area,” as declared by SC in Nahalchand Laloochand Pvt. Ltd. Issue a lawyer's notice to RAW marking copy to obstructor of space warning of legal action with costs of litigation with interest. You can also complaint to Deputy Registrar of Societies if the RWA is registered. If they realize that you are sure to seek legal remedy against them, they will rectify. Everyone is scared of law. 

- As per rule , the Association  shall  frame  rules,  regulations  and  procedures  for its common areas and facilities as well as frame guidelines of restrictions and measures designed to prevent the unreasonable and improper use of facilities and common areas  which  will  interfere  with  the  peaceful  occupation  of  units  by  respective  Owners  / Residents conducive to day to day living environment. 

-  Further,no sructure  of   any  kind  whatsoever  temporary  or   permanent  shall  be  erected  or fence/partition  put  up  on  any common  area  that  may  obstruct,  or  impede  free movement in the event of an emergency of any kind. In addition, on the Limited Common Areas adjoining the ground floor flats 

- Hence, the said acts of neighbour is against the rule of law. and the association /RWA is bound to take legal action against him 

- If the RWA is not taking any action against him , then you can lodge your compliant before the registrar , and a compliant against the neighbour to the local municipal corporation. 

- Further, you can also file a suit for Injunction before the court against the said person and RWA for taking action against him. 

 I the same is illegal as per the model bye laws and you can complain about it before Dy registrar of co-operative society 

Dear client,  

I'm not a legal expert, but I can provide you with some general suggestions for addressing the issue you described. It's important to consult with a local lawyer who specializes in property and neighbor disputes to get specific advice based on the laws and regulations in your jurisdiction. Here are a few options you could consider:

Review the governing documents: Examine the governing documents of your residential complex, such as the bylaws, covenants, or rules and regulations. These documents may outline specific guidelines regarding the use of common spaces, balconies, or exteriors of the building. If the neighbor's blockage violates these rules, it could provide a basis for action.

Mediation or arbitration: Explore the possibility of mediation or arbitration to resolve the dispute. This involves engaging a neutral third party who can facilitate discussions between you and your neighbor in order to find a mutually acceptable solution. Mediation or arbitration can be less formal and costly compared to litigation, and it may help in reaching a resolution.

Send a legal notice: Consult with a lawyer to draft and send a legal notice to your neighbor, informing them of the violation and requesting them to remove the blockage within a specified timeframe. A legal notice can often convey the seriousness of the matter and prompt action.

File a complaint with local authorities: If the blockage poses health or safety risks, you may consider filing a complaint with the appropriate local authorities, such as the municipal corporation or health department. They may have regulations or guidelines in place that govern such issues, and they can initiate an investigation or enforcement action if necessary.

Seek a court order: As a last resort, if all other options fail, you may consider filing a lawsuit in a civil court. Consult with a lawyer to assess the strength of your case and determine if legal action is appropriate. The court may issue an order requiring your neighbor to remove the blockage and restore the common space.

Remember that the specific legal options available to you may depend on the laws and regulations in your jurisdiction, as well as the specific circumstances of the situation. It's crucial to consult with a legal professional to understand the best course of action based on the applicable laws and your specific case.

The said common area is common for all and do not belong to any particular member/owner for the complex.

You have all the rights to use this common area without disturbing other members of the association.

Similarly if someone indulges in the illegal activity of blocking the common area, and if the association is not taking any action on this despite making a complaint, you may issue a legal notice to the association and to the arrogant neighbor too.

If this is not fetching you the desired results you may file a complaint against the society with the deputy registrar o cooperative societies to intervene and provide relief as per law.

You can also plan to escalate the matter to the civil court or cooperative court with a suit for mandatory injunction against the neighbor if you still don't find any relief anywhere.

Common areas are for use  by all residents and no one is allowed to occupy it to keep personal things for a long time. You should take it up with the RWA stating that it is obstructing your free movements and creating nuisance. You may need to give it in writing and raise it in the meeting of the RWA. If the RWA does not respond and that flat owner is not directed to remove the stuff, you may make a complaint to local authorities stating that in case of fire and other emergencies it will obstruct free movements and thus it is hazardous.  If the RWA is registered, then you may complain to the registering authority.

Send  a notice to both the violator and the RWA through a competent lawyer. If there is no redress, file a suit at the proper court seeking appropriate orders.