Margaret Thatcher is said to have stamped her foot in anger

He says his poor relationship with Margaret Thatcher, for instance, made it difficult to deal with her opposition to German reunification.

He says Mrs Thatcher stamped her feet in rage about the issue, days after the fall of the Berlin Wall.

Mr Kohl was chancellor from 1982 to 1998, overseeing reunification in 1990.

The BBC's Ray Furlong, in Berlin, says Mr Kohl reflects on the strong opposition to reunification from the UK and France in these, his second volume of memoirs.

The Thatcher incident was said to have taken place during dessert at a dinner in Paris nine days after the fall of the Berlin Wall in 1989.

Later, he says, she threatened to use her veto against reunification in the then European Community.

Bush support

Our correspondent says Mr Kohl was surprised by his ally Francois Mitterrand also resisting German reunification. But the former chancellor tells how he persuaded the French leader to change his mind during long private walks on the beach near Bordeaux in January 1990.

US President George Bush, though, was apparently a staunch supporters of the idea from the very beginning.

"George Bush was for me the most important ally on the road to German unity," Mr Kohl writes.

"We were united not only by political respect for each other, but also by deep mutual sympathy as people."