Media playback is unsupported on your device Media caption Post-Brexit deals 'not at price of EU free trade ties'

Post-Brexit trade deals should not "come at a price" to existing agreements with other EU nations, ex-chancellor George Osborne says.

But he told the BBC's Andrew Marr the UK needed a "hard-headed assessment" of issues such as the EU customs union.

On the same programme, International Trade Secretary Liam Fox did not reveal his stance on the customs union, which sets standard tariffs EU-wide.

He said he was "a free trader", but the government would reach a view.

Staying a member of the customs union would, however, mean "limitations" on the UK's ability to set its own trade tariffs, which would in turn limit the kind of deals it could do with the rest of the world, Mr Fox added.

Who has access to the single market?

What are the UK's post-Brexit trade options?

Mr Osborne, who argued for Remain, said it was essential that close relations with countries such as France and Germany were not sacrificed in pursuit of new trade deals with other nations including China.

He told the Andrew Marr Show: "Yes it's true the grass may be greener outside of these arrangements and we may be able to conduct new trade deals with the United States, Australia and so on.

"But that shouldn't come at a price of giving up existing free trade agreements we have with Germany and France.

"You can't say we are a beacon of free trade in the world and then the main thing you achieve is a huge act of protectionism, the biggest in British history."

'Boiled egg'

Mr Osborne - who lost his job in the cabinet after the referendum - admitted the Remain campaign lacked "some of the authenticity and optimism" of the Leave camp, and focused too much on dire predictions.

"We discovered there was not much out there in terms of support for European friendship and so we ended up talking a lot about the economy and, as chancellor, of course, I was centre stage in that."

He also said the pledge to get net migration down to the tens of thousands "damaged" the government in the referendum because "we didn't really have an answer" when challenged on why it had been missed.

What is the customs union?

In the EU customs union no customs duties are paid on goods moving between EU countries

All countries also apply a common customs tariff for goods imported from outside the EU

Goods legally imported into one country can circulate throughout the customs union with no further customs checks

Mr Osborne said he hoped the predictions he made about the economy post-Brexit turn out "not to be true."

But he told the programme he would "wait and see what happens" as the pound had fallen sharply since the referendum and Britain was "poorer as a result".

Also speaking to Andrew Marr, Mr Fox said Brexit the question of the customs union was "not binary".

"I hear people talking about hard Brexit and soft Brexit as though it's a boiled egg we are talking about, it's a little more complex. So, Turkey, for example, is in part of the customs union, but not in other parts."

Media playback is unsupported on your device Media caption International Trade Secretary Liam Fox: 'I'll argue my case inside cabinet'

Mr Osborne's appearance on the show marked his first TV interview since he was sacked by Prime Minister Theresa May.

He said he had "learned a lot" during his time as chancellor and wanted to attempt to understand what he had got right and what went wrong.

During the London 2012 Paralympics he was booed while handing out a medal, which he admitted "hurt", particularly as his children were in the crowd.

But he added: "Sometimes those moments do help change you for the better."

He said his work trying to promote a Northern Powerhouse was also allowing him to travel around the country and attempt to "understand why people feel the system is not working for them".

Earlier this week, the former chancellor told a Commons debate British MPs were deceiving themselves if they thought they did not have some responsibility for what had happened in Syria.