Polish president Aleksander Kwasniewski has been given a full ceremonial welcome to Britain by the Queen.
The Queen will host a banquet for Mr Kwasniewski
The three-day state visit by Mr Kwasniewski and his wife follows the accession of Poland to the European Union on 1 May.
The president was also greeted by Tony Blair, Foreign Secretary Jack Straw and Home Secretary David Blunkett on Wednesday after a parade down the Mall.
Mr Kwasniewski also laid a wreath at the Polish War Memorial at Northolt.
The Household Cavalry and 1st Battalion Grenadier Guards were present for the ceremony which included the Queen travelling in a closed carriage for the horse-drawn procession along The Mall to Buckingham Palace.
Capital - Warsaw
Population - 38.6 million (UN, 2003)
Major language - Polish
Major religion - Christianity
Local currency - 1 zloty, equal to 100 groszy
Communist rule - overthrown in 1989
Nato - joined in 1999
European Union - joined in May 2004
Earlier, the president and his wife, Jolanta, were met at Heathrow Airport by the Prince of Wales who accompanied the visitors to London by car.
After meeting Polish and British RAF veterans from World War Two at Northolt, Mr Kwasniewski and the prince briefly spoke to members of the Polish Air Force
Association, including its vice president, Colonel Andrzej Jeziorski.
Afterwards Col Jeziorski said: "I just mentioned to the Prince about how
many names there were on the memorial. There are almost 2,000 names of Polish
airmen that lost their lives during the war."
Many Polish airmen left their homeland to fight for the Allies after their own
country was occupied by the Germans.
Col Jeziorski said it was very important that the president had visited the
"It is not his first visit but it is the first official visit to this country.
"The first thing he has done is to pay homage to the Polish airmen
that lost their lives in the war."
Mr Kwasniewski is a former communist, who once worked behind the bar of a London pub and is an ardent Arsenal fan.
During his three-day visit he will visit the football club's home in Highbury, north London, as well as attend a state banquet hosted by the Queen at Buckingham Palace.
The 50-year-old president, who - like his lawyer wife speaks English - last
visited Britain in July 2002 when he had talks with Mr Blair.
It is the second state visit by a Polish head of state, following that of
former Solidarity leader Lech Walesa in 1991.
With a population of almost 40m, Poland was the biggest of 10 countries to join the newly enlarged EU.
It was the first of the eastern European countries to overthrow Communist rule in 1989, going on to join Nato in 1999.