LONDON — Theresa May is due to set out her government's plans for Brexit at a speech on Friday afternoon. The long-awaited speech, which is titled "Our Future Partnership," is expected to start around 13.30 GMT. So what can we expect to hear from the prime minister today and what can't we?

What she won't say: "It's great to be here in Newcastle"

Wintry conditions have altered the prime minister's plans Jeff J Mitchell / Getty The speech was due to take place in the North East of England but the plans were cancelled after some of the heaviest snow for years. Business Insider understands that Downing Street spinners were concerned that journalists on the way up from Westminster would have ended up stranded on northbound trains.

What she will say: Welcome to London

According to May's spokespeople: "In a speech at London’s Mansion House, the Prime Minister will return to the words she delivered on the steps of 10 Downing Street in July 2016, when she pledged to 'forge a bold new positive role for ourselves in the world and… make Britain a country that works not for a privileged few, but for every one of us'."

What she won't say: "We're staying in the Customs Union"

Michel Barnier on the Northern Ireland border Charles McQuillan / Getty Conservative rebels, the Labour party and the EU, have all been piling on the pressure this week in an attempt to persuade Theresa May to reverse her decision to leave the current EU customs union and rule out joining any new form of customs union with Europe. However, there is little sign that this will be on the cards today based on the extracts from the speech sent to the British media overnight.

What she will say: The UK must "take control of our borders"

May will insist that the final Brexit deal "must respect the result of the referendum," adding that the vote in 2016 was a mandate to "take control of our borders, laws and money." That means no continued close alignment with EU customs rules, as demanded by the EU and Conservative rebels.

What she won't say: "A binding commitment to EU rules"

Theresa May's Cabinet met yesterday morning to discuss the contents of the speech. Each cabinet member was given a paper copy and told to study it for around 20 minutes before the discussion began. While most of the content of the speech had already been agreed in earlier meetings, there was some concern among Cabinet Brexiteers about a line in it suggesting that the UK would make a "binding commitment" to align to EU rules in some sectors of the economy. According to the Spectator, both the Brexit secretary David Davis and the foreign secretary Boris Johnson objected to this and so the section was altered. A Downing Street spokesman told Business Insider on Thursday that the cabinet had a "genuine discussion" about the content "ahead of the speech being finalised" later in the day.

What she will say: I will make "strong commitments" to follow some EU rules

According to the Times, the reference to "binding commitments" has been removed from the speech and replaced with "strong commitments" instead. So how binding is a strong commitment and how strong is a binding commitment? It's not entirely clear. However, what is clear is that May will spell out her government's aim of achieving a so-called "three baskets" deal with the EU, whereby Britain would remain closely aligned in some parts of the economy but not others. But as Business Insider's Thomas Colson explained last week, this has already been ruled out by the EU.

What she won't say: "We're staying in the ECJ"

Theresa May and Jean-Claude Juncker AP Photo/Virginia Mayo In her speech today May will state that Britain must leave the jurisdiction of European courts, insisting that the UK and EU must become "two separate legal systems".

What she will say: We must stay in some European agencies

As the BBC's Laura Kuenssberg reveals, May will suggest that the UK could keep "associate membership" of various European agencies in industries such as aviation and pharmaceuticals. This will be a relief to the aviation sector, some of whom have previously expressed concerns that Brexit could leave Britain in a regulatory no-mans land in which planes are literally not allowed to take-off.

What she won't say: "Here is exactly what Brexit will look like"

Theresa May and Conservative MPs Jack Taylor / Getty Those hoping for May to spell out in great detail the terms of the Brexit deal Britain is seeking will be disappointed today. The excerpts released overnight are heavy on warm words about maintaining a "strong relationship" with Europe, but low on specifics about exactly what Britain's future outside of the EU will actually be.

What she will say: "These are my five tests for the deal"

May will instead set out 5 tests for any Brexit deal. These are that it will:

Implement the decision of the British people

Reach an enduring solution

Protect our security and prosperity

Deliver an outcome that is consistent with the kind of country we want to be

Bring our country together and strengthen the precious union of all our people

If that all sounds rather vague to you, you'll just have to come back to Business Insider this afternoon for more details on what each of those tests actually mean.