Turkish President Recep Tayyip Erdogan has accused the US of trying to "bring Turkey to its knees through threats over a pastor".

The US has demanded the release of Andrew Brunson and on Friday doubled tariffs on steel and aluminium imports.

The diplomatic spat sent the lira down 16% against the dollar on Friday.

Mr Erdogan also wrote in the New York Times that unless the US changed course, Turkey would look for new friends and allies.

Turkey has detained Mr Brunson for nearly two years, accusing him of links to the outlawed Kurdistan Workers Party and the Gulenist movement, which Turkey blames for a failed coup in 2016.

But the pastor is only one of a number of issues dividing the two Nato allies, including policy on Syria and Mr Erdogan's growing ties with Russia.

What are Mr Erdogan's latest comments?
He was speaking at a rally in the Black Sea town of Unye.

He said: "It is wrong to dare bring Turkey to its knees through threats over a pastor. I am calling on those in America again. Shame on you, shame on you. You are exchanging your strategic partner in Nato for a priest. You can never bring this nation in line with the language of threats.

"We have not made concessions on justice so far, and we will never make any."

Turning to the economic effects of the diplomatic row, Mr Erdogan said: "If they have the dollar, we have Allah."

He added: "If there are dollars under your pillow, take these out. If there are euros, take these out. Immediately give these to the banks and convert to Turkish lira and by doing this, we fight this war of independence."

And in the New York Times?
Mr Erdogan said the US had "repeatedly and consistently failed to understand and respect the Turkish people's concerns".

He added: "Unless the United States starts respecting Turkey's sovereignty and proves that it understands the dangers that our nation faces, our partnership could be in jeopardy."

Mr Erdogan said although the nations had been allies for decades, Turkey "now has alternatives".

"Failure to reverse this trend of unilateralism and disrespect will require us to start looking for new friends and allies."

He also condemned as "unacceptable, irrational and ultimately detrimental", the sanctions imposed by the US on several Turkish cabinet members over the Brunson issue.

What are the other issues of disagreement?
There are quite a few, a number of them addressed by Mr Erdogan in the New York Times.

He is clearly angry that the US has not taken more action against the Gulenist movement and what he said was a failure "to unequivocally condemn" the 2016 coup attempt. The US has refused to extradite Fethullah Gulen, who lives in Pennsylvania.

US support for Kurdish rebel groups fighting Islamic State fighters in northern Syria. is another major difficulty, given Turkey's battle against a Kurdish insurgency in its own country.

On Friday Turkey made it clear Mr Erdogan had spoken on the phone with Russian President Vladimir Putin after the latest US tariffs, with the two men "expressing pleasure" that relations were progressing "positively".

It's an awkward triangle, given that Turkey is a Nato member, Russia is Nato's number one threat and the organisation is obliged to defend any member that is attacked.

Nato uses the Incirlik Air Base in Turkey to fight against IS and there has been some domestic pressure on Mr Erdogan to close it.

What were the latest US measures?
President Donald Trump doubled US tariffs on Turkish steel and aluminium, saying "US relations with Turkey are not good at this time".

The reaction from global currency markets caused the euro to slump to a 13-month low and pushed the dollar to a one-year high.

American evangelicals have pressed Mr Trump for action on Pastor Brunson, who was held in prison for almost two years but was recently moved to house arrest.

Turkey has also been hit by US sanctions on Iran, given that half of Turkey's oil imports come from Iran.