How To Split The Property ?

I'm seeking solution on how to split property between siblings A and B
When B moved to USA(28years back)he sent money every month(for 8 years) and a house was bought under B's name. This is single family home. A was working in high level government job during that time. Since parents were in India they lived with A in the same house without rent. 2 years later A found a very good deal for a plot next to B's home. Since A had a bribery case filed against him A bought the property under the mom's name. This situation continued for two decades. Once mom died A(Retired by now) wanted this land and other mom's property(in village) to be transferred under his name. B went to India signed all the papers and transfer was done. During pandemic A came up with a plan to build a two storey home by demolishing building of B and joining his land. He gave a proposal where he will bear the construction cost but he needs only B's land to be shared . B's land is 250square feet more than A's. His opinion is right now there is no car parking in B's plot and if he has to build a building with car parking he cannot have a spacious building. Since B didn't liked this proposal he asked A to vacate the building and handover the documents and keys. A came back with another proposal saying 20 years back 1/4th cost was given by him hence he would like to buy A's house(this is first time B is hearing this news) and he offered 50% off market prize second option was he offered to give his land to B and get B's apartment(2x cost of land). B wasn't aware of investment by A in that house(for 20 years) and mom isn't alive to confirm if it is true. A has possession of the house document(registered under B) and keys and is refusing to part with him. Since A has worked in government(retired) he also sent threatening message to B to accept one of the proposals . B has no plans of selling his home and he feels he didn't enjoy any benefits for buying the home till now. He also feels he didn't get any share for any of mom's property and this information should have been disclosed during initial signing and not now.

B has a option to sell the home by-passing the brother but that will take time since home hasn't been fixed/pained and with keys being in A's possession he cannot do much.

B has used common family members to talk to A but he is refusing to back down.
What is the best solution that can be availed by A and B in this situation ?