Many Zimbabweans have expressed shock on social media after President Robert Mugabe ended a much-expected national address on Sunday without announcing his resignation.

Mugabe, who has been leading Zimbabwe for 37 years, has been under increasing pressure to relinquish power following a surprise military takeover earlier this week.

On Saturday, thousands of people took to the streets of the capital, Harare, calling on the 93-year-old leader to resign and showing support for the military's action.

Mugabe was widely expected to announce his resignation in the televised address but defied expectations by pledging to preside over a ruling ZANU-PF party congress next month instead.

On Twitter, some conveyed anger at having the protesters' demands ignored.

I am extremely angry and disappointed. How could Mugabe rumble like that.. he should have not wasted our time... we want him gone. People have spoken "Ngaende Ngaende Mugabe!" Mr President stop denying us our Freedom. Stop defying the country. — Tau Moyo (@TauraiMashiriMo) November 19, 2017

Mugabe even went on to say Goodnight. What is good about this night? We will meet you tomorrow in the streets! #Mugabe #Zimbabwe — Protesting Graduate. (@TKMRushwaya) November 19, 2017

#mugabe l feel cheated — Tinomuda Maria Shiri (@MariaShiri) November 19, 2017

One of the things Mugabe has taught us is to be patient. Congress is in a few weeks. People can wait especially after waiting for 37 years. — daniel ngwira (@danielngwira) November 19, 2017

On Facebook, one person said:

Others simply poked fun at the situation.

We just got played by mugabe 😧 — Hillary mandibaya (@Hillarymandyzw) November 19, 2017

The world has just given the Mugabe free air time — Zimbabwe Community (@ZWcommunity) November 19, 2017

I think Mugabe forgot to read the part where he resigns 😂😂 — Terrell Demorgan (@TerrellDemorgan) November 19, 2017

Al Jazeera's Haru Mutasa, reporting from Harare after Mugabe's speech, said "a lot of people are surprised" he did not step down "after all this pressure".

"Sources behind the scenes say that he is being stubborn and for now he isn't going anywhere," added Mutasa.

"The thing to watch now is the Monday midday deadline when, if he doesn’t step down, then they will impeach him in parliament."