Following on from his earlier film clip, here is Nick Clegg’s email to party members:

Dear member,

Tomorrow Parliament will consider international action in Syria.

I have been adamant from the outset: any case for international action must be taken to the UN in an effort to achieve as great an international consensus as possible. And I have made certain this is taking place.

We must wait until we hear from the weapons inspectors.

Ahead of tomorrow’s debate, you can read the full wording of the motion we’ll be laying before Parliament here.

For the past week I have been in regular discussions with the Prime Minister, with Ed Miliband and with international partners such as Vice President Biden in America.

All sides agree, the murder of innocent men, women and children through the use of chemical weapons is a war crime and a crime against humanity. It is a repugnant crime and a flagrant abuse of international law.

It is important that we try to do everything we can to ensure international and cross party consensus. That is why we have listened to EU countries and the Arab League, why we are taking this to the UN and why we are ensuring the House of Commons has the final say before any direct British involvement – one vote tomorrow, and another one if and when we are asked to participate directly.

As we consider action, I am clear, we must only consider measures which are legal, which are proportionate, which have as much international backing as possible and which are specific to stopping the use of chemical weapons. These are weapons which are indiscriminate in their killing and have been prohibited under international law for generations.

I understand the anxiety which the possibility of military action generates after our experience of Iraq – an illegal war opposed in Parliament by Lib Dems alone.

But this is not Iraq. Here are 5 reasons why:

The use of chemical weapons is a war crime and there is no disputing these weapons have already been used. We are working in lock-step with our international partners, with France, the EU, the Arab League and Turkey and a Democrat President in the United States. Proportionate, targeted military action following a regime’s use of chemical weapons is legal under humanitarian law. This is not about boots on the ground. This is not about regime change. This is about upholding international and humanitarian law and deterring the use of chemical weapons to protect innocent people from being murdered in future by brutal dictators. There will be a vote in the House of Commons. We have gone to the UN, and the Attorney General is publishing unedited advice based on evidence.

I joined the Liberal Democrats in no small part because of the Party’s internationalist and humanitarian values. I don’t believe anyone who shares these values can stand back and watch what is currently happening in Syria. As in Sierra Leone and Kosovo, this is a moment for Liberal Democrats to stand up for our values and act, upholding international law and protecting the people of Syria from the worst excesses of authoritarian oppression.

Nick Clegg

Leader of the Liberal Democrats and Deputy Prime Minister