After the talks, a Number 10 spokeswoman said:
The meeting reaffirmed the existing strong and historic bonds between the UK and Gibraltar and the Prime Minister repeated his commitment to stand shoulder to shoulder with the people of Gibraltar.
They discussed the unacceptable delays at the Spanish/Gibraltar border and agreed that these are damaging to the people and economies of Gibraltar and Spain.
They agreed that efforts should remain concentrated on finding a diplomatic solution, in line with the Foreign Secretary's proposals last year for ad hoc dialogue.
David Cameron has met Gibraltar's Chief Minister Fabian Picardo at Downing Street to discuss the UK's border dispute with Spain.
- Mr Picardo's visit to the UK saw him meet with Foreign Secretary William Hague on Wednesday, a meeting he said showed that the UK and Gibraltar governments "remain in lockstep" over the disagreement.
- The spat effects regular commuters as up to 8,000 Spaniards living mainly in the nearby towns of La Linea and Algeciras travel daily to Gibraltar for work.
- Yesterday, the Gibraltar government accused Spain of introducing an export ban on construction materials to punish the enclave.
A Royal Gibraltar Police (RGP) spokesman said it received an "unofficial report" from the Guardia Civil on Wednesday about missiles being thrown at its officers from the motorcycle lane, as well as verbal abuse.
However, RGP were "unable to substantiate" accusations and continuing to investigate.
– A Royal Gibraltar Police spokesman
This has allegedly taken place at the peak of extensive queues to exit Gibraltar which at their height reached four hours.
The alleged missile throwing is reported to have come from the area of the motorcycle lane which at the time was full of cross-border workers unable to return home.
It came after insults and abusive comments were directed at the Guardia Civil.
The RGP is, notwithstanding the number of RGP officers present at the frontier managing the traffic, unable to substantiate the complaint at this time.
The matter is under investigation.
The diplomatic spat with Spain over Gibraltar takes another turn later today when David Cameron meets with Fabian Picardo, the chief minister of Gibraltar.
The Downing Street meeting comes the day after Spanish Guardia Civil officers claimed they were pelted with stones by angry commuters held at the border crossing.
Delays of several hours have continued intermittently in recent weeks, caused by stringent checks imposed by the Spanish during the diplomatic row over an artificial reef sunk off Gibraltar.
Gibraltarians claim 74 concrete blocks on the seabed were necessary for environmental reasons, but the Spanish say they disrupt an area used by fishing boats.