This is the Global News Podcast from the BBC World Service.

I'm Nick Miles, and in the early hours of Sunday, the 19th of January, these are our main stories.

Just hours before an imminent ceasefire in Gaza, Benjamin Netanyahu has said Israel reserves the right to return to war if further negotiations collapse.

Nigerian officials say at least 70 people have been killed

after a fuel tank had crashed and exploded northwest of Abuja. Thousands of people have

protested in Washington against the incoming President Donald Trump. He's begun a series of

celebrations ahead of his second inauguration on Monday.

Also in this podcast,

The discovery that oxygen, which is vital for life,

was being made in the dark on the seafloor,

confounded marine scientists when it was announced.

So what else do we know about dark oxygen.

We begin in the Middle East.

And as we record this podcast, it is just hours before the imminent start of a ceasefire between Israel and Hamas.

It begins with a six-week pause in the fighting and a prisoner-hostage exchange,

the first of which is due to take place on Sunday. Under the deal,

humanitarian aid will also be allowed into Gaza. Subsequent phases will include more hostage and

prisoner exchanges and eventually the long-term reconstruction of Gaza. In a speech, the Israeli

Prime Minister Benjamin Netanyahu stressed that the agreed ceasefire was temporary,

and Israel, with the backing of the United States,

reserved the right to resume the war against Hamas.

Before the next phases, we are keeping very significant assets in our hands

...