Termination of an off-plan property contract for delay in delivery

I bought a one-bedroom apartment in 2015 for AED 1.04 m with a completion date of June 2017. I had paid 40% of the price, and 60% (AED 625,000) was to have been paid on completion in two years (2017).

The project has been delayed significantly, and when I visited the apartment at the end of Feb 2020, it was not ready.

The developer now claims to have received the BCC from the Dubai Land authorities and hence wants full payment of the balance AED 625,000. They claimed the property is ready for handover, but it needs work to be habitable.

I am a British citizen, and my own situation has changed in the five years since. I kept the 60%, but since then, my financial situation is such I no longer have the 60% of the fund AED 625,000 to pay them.

I can't get the remaining as a mortgage for as an expatriate, I can get a maximum of 50% of the value which is now only AED 750000 max.

How can I get compensation and my money back from the developer?