I remember when I was in Sana, Yemen's capital, in 2013, and I was with some tribesmen who were protecting me, who came from the east of the country where I work.

And whenever we heard gunfire or shots,

which isn't uncommon in Sana,

they would fall about laughing, saying,

al-Hawar al-Watani, which means the national dialogue,

because to them it was completely obvious

that this was a civil war in waiting. We in the West, we were the only ones who hadn't sussed that yet.

But we in the West are beginning to suss it now.

As the House, we'll be aware, Yemen is one of the most serious humanitarian crises in the world.

The tragedy for me, and that's why you have these proxy wars being fought the whole time in that

area, is that there's not strong enough leadership in the countries themselves.

Civil war in Yemen has become a full regional conflict with global implications.

But what on earth is it all about?

Finding out the answers to questions like that is what the briefing room is for.

And joining me in it today to discuss the war, a Dr Elizabeth Kendall, who splits her time between teaching Arabic at Oxford and hanging out with armed tribesmen in Yemen, and Safar al-Ahmad, a Saudi Arabian filmmaker and journalist who's reported from Yemen's front lines.

I'll be talking to Safar about her experiences in a moment, but first, some basic information.

Elizabeth Kendall, what is Yemen?

Yemen is a relatively new invention. It only came together as a whole country in about 1990.

And already four years later, there was a civil war between the north part of the country and the south.

But Yemen is also the poorest country in the Arab world.

Why would we therefore care about it?

Well, it's quite populous.

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